Temperate staple crops: plants (and critters) for a future

In my review of Carol Deppe's annual-based The Resilient Gardener, I expressed disappointment that no one has created a comparable blueprint with perennials. Now that I've moved to Hawaii with its abundance of well-documented perennial crops, I've dramatically eased my own task of synthesizing perennials, animals, and wildlife into production of a low labor, landbase supportive paleodiet. But I still want to see similar systems develop in temperate areas. I can offer some hints and glimmers of hope based on my experiments in Portland, for others to develop further. My previous post, Low-Maintenance Temperate Staple Crops, established a broad framework. This post gives more specific suggestions, heavily biased towards a Pacific Northwest climate with its winter rains and summer drought.

Livestock

Small parcels

• Most importantly, experiment with ways to integrate small animals such as ducks, chickens, rabbits, and guinea pigs into perennial gardens in such a way that the animals benefit the system, require minimal care, and produce high quality eggs & meat.
• Keep bees for honey for moderate consumption. They'll gather incredible numbers of calories for the space required.
• If you have a pond, try growing fish, even if just goldfish for slow-growing, very occasional eating by yourself or poultry.

Larger parcels

• Keep grazers such as geese, sheep, buffalo, and cattle where the land wants to grow grass.
• Keep browsers such as goats where the land wants to grow trees. Manage them carefully to ensure they don't make the land grow dead trees and sad scrub.

Tree crops

• Plant nuts. Chestnuts, acorns, english walnuts, black walnuts, filberts, and ginkgos have all proven themselves as reliable abundant croppers in the PNW.
• Plant fruits & berries. Figure out how much you can realistically eat, and how much is healthy for you.
• Grow olives if you can, for low-PUFA, oil rich food. Our olives failed to grow, but others in the Portland area have had success. We may not have given our plants good enough drainage.
• Use the seed kernels from Prunus and other fruit species as bonus seeds for your own or livestock consumption.

Herbaceous seed crops

• Good King Henry (Chenopodium bonus-henricus): needs breeding work for increased seed production (larger and/or more seed.) We found it a very low maintenance and tough crop, though we didn't perfect a ground cover situation to eliminate the need for spring weeding. Seed yields never got very high for the land involved - perhaps partly from competition following our neglect in weeding, and partly from inadequate irrigation in the summer.
• Scarlet runner beans (Phaseolus coccineus): try growing them as perennials. We never succeeded in growing them well even for the first year (slug pressure?), and the few healthy plants didn't overwinter. Someone in my neighborhood grew them as perennials on the west side of his house for summer shade, so maybe giving them a similar warm microclimate and/or heavily mulching would help. Breeding for hardiness may help. Supposedly you can dig up the roots and store them in a root cellar, then replant in spring.
• Experiment with recently developed perennial grains for humans (assuming you can digest them OK) and/or animals.
• Integrate minimal maintenance legumes like overwintered favas and early spring peas (we had minimal success with these - ducks to keep down our slugs may have helped). As with the grains, humans can eat these in moderation if they don't have bad reactions, and/or they can feed livestock.
• Perennial flax (Linum perenne). We grew this on our ecoroof and got a few seeds the first year. We didn't stay long enough to know whether it produces well once fully established. If not, maybe it could benefit from breeding work. Like its annual relative, perennial flax oil is rich in omega-3, highly beneficial for us and for livestock.
• Find other perennial seed crops for minor or major production. For example, we found fennel extremely easy to grow and harvest for ourselves and for the chickens, but we could only eat a small amount of seed each day because of its strong flavor. Perhaps a variety of minor seed crops could add up to useful caloric inputs.
• Breed other perennial legumes for larger or more useful seeds for humans, or just plant them as livestock fodder - Lupinus perennis, Vicia cracca, Vicia americana, black locust (Robinia pseudoacacia), pea shrubs (Caragana sp.), and ...?

Root crops

See my notes on perennial and self-seeding roots for more information on specific species: part 1 and part 2.

• Jerusalem artichokes AKA sunchokes (Helianthus tuberosus): Fantastic drought tolerant, persistent, low-to-no-labor abundant yielder. Due to high inulin content, these only work well as a staple crop if you can either:
  • Digest them OK with minimal cooking (many people ferment them).
  • Cook them long enough on a wood stove running in the winter anyway.`
• Skirret (Sium sisarum): breed for increased root production. We found yields quite reasonable at 1/2 pound/year in good conditions, and 1/4 pound/year in shade or poor soil. We experienced enough variation in yields between different plants to warrant selecting for larger and more roots. Skirret also deserves experimentation with different lengths of multi-year growth before harvest to maximize its potential as a perennial; we generally found the roots larger and less woody if we let the plant grow for two or three years, but never quantified this precisely.
• Grow mashua (Tropaeolum tuberosum), oca (Oxalis tuberosa), and yacon (Polymnia sonchifolia) as perennials, deep mulching as needed to overwinter them.
• Where conditions allow, try aquatic crops like cattail, water chestnut, and wapato.
• Develop and refine perennial polycultures such as my experiments with skirret/oca/potato and yellow asphodel/oca/lily.
• Cinnamon vine (Dioscorea batatas): great potential as a no-dig staple carb from its aerial bulbils. Set up on a permanent trellis such that you can lay a tarp or sheet under the vines to easily collect lots of bulbils at once.
• Creeping bellflower (Campanula rapunculoides): summer available root with mild flavor from an aggressive ground cover. May work well under jerusalem artichoke.
• Yellow asphodel (Asphodeline lutea): summer-available root adapted to summer drought and intercropping well with many other plants. Try to breed it for larger roots (perhaps at the expense of its flowering, which though beautiful and providing tasty nibbles presumably diverts a lot of energy from the roots.)
• Scorzonera (Scorzonera hispanica): experiment with how long to leave in the ground without having to dig too deep for the taproot. I tended to dig the top foot or so of the root, but snapped it off and lost it below that point. Experiment with replanting a portion of the tops instead of needing to resow from seed. I have successfully transplanted individuals with 6-12" of root, but suspect you could plant even less, and therefore get to eat more.
• Asiatic lily (Lilium sp): I assume Asian growers bred these over thousands of years to select for larger bulbs from these gourmet crops. Seek out varieties with maximum food yield instead of showiest flower.
• Camas (Camassia sp.): Another inulin rich root, requiring experimentation in a solar cooker to evaluate as a summer staple root. Otherwise it may not be justifiable due to the large amount of fuel required to make it digestible.
• Garlic (Allium sativum): pseudo-staple (since you can only eat so much of it per day.) Super easy to grow and supposedly high in calories per pound, though I wonder whether the high inulin content means we don't actually digest all the calories.

A Good Egg Is Hard To Buy

With our hens in low production over the winters, we regularly resort to buying in some eggs. The quality always disappoints me. Even local, pastured eggs at $6 and $7 a dozen literally pale in comparison to those of our hens! Maybe this is one of those things money can't buy--at least not in commercial quantity?

The picture shows our hen egg at left, and one each of the $6 and $7/dozen eggs at right.  (Plus other standard ingredients of my scrambles: cooking greens, acorn halves, cherry kernels, and skirret root.  Fennel seed is in there but too small to see.  Garlic to be added at the end.)

Fall 2011 Garlic Plantings

Today I planted the new batch of garlic. I'm writing up notes as a hard copy of what got planted where, but also figured I'd document it here. See also my post documenting last year's harvests and observations on yields.

When I harvested the elephant garlic from the ecoroof in the summer, I replanted a bunch of the little tiny bulblet offsets, not knowing whether we'd still be here in the fall and how busy we or new owners would be, and how well organized for planting new cloves. I figure I'll keep an eye on those patches as the bulblets sprout, and plant some larger cloves in any thin areas. I'll plant the shallots on the ground somewhere; I still need to figure out their destination.

I planted 11 varieties of true garlic, all on the sunspace and front porch ecoroofs. Since our garlic plants didn't seem to be limited by soil depth last year, I spaced the cloves at 6" this year instead of the 8-12" of last year, hoping they still won't run into soil competition limitations. I planted 50 cloves of each variety (with three exceptions), using one "patch" of 9 sq. ft on the front porch or 12 sq. ft on the sunspace for each variety. I switched last year's three patches of shallots over to garlic this year. I planted a total of ~550 cloves, compared to about 175 on the ecoroofs last year.

I weighed the planting cloves to give a better understanding at harvest time next year of how much input was required for the yield.

Variety	Roof	Patch	# bulbs	Weight (oz)	Notes
Spanish Roja	Sunspace	North side center	50	5.25	Relatively small cloves
Mild French Silverskin	Sunspace	Far NE	~80	8.25	Relatively small cloves
Polish Jenn	Sunspace	South side center	50	17.75
German Porcelain	Sunspace	SE of chimney	50	16.75
Inchelium Red	Porch	1st stepping stone area on south side	50	4.75	Small cloves
Unknown #2 (Porcelain group?)	Porch	SW most garlic patch	50	22
Italian Late	Porch	North side, second most from west (west-most north patch with garlic actually in it)	~35	2	Small cloves
Musik	Porch	North side, third most from west (second west-most north patch with garlic actually in it)	50	7	Relatively small - one more year of growing out should provide larger seed cloves
Nootka	Porch	North side, just east of center (east of Musik)	~38	2	Small cloves
Appalachian Red	Porch	North side, second from the far east	50	7.75
Unknown #1 (Porcelain group?)	Porch	North side, east most patch	50	12

Garlic & shallot harvests: ecoroof and yard

The Experiment

Test locations

Last fall I planted garlic and shallots in the yard and on the sunspace and front porch and ecoroofs:

• Sunspace ecoroof: 5.5" of soil medium. Slight south slope, and heated living space below, full sun. (Photo at left.)
  
• Front porch ecoroof: 8" of soil medium. Slight north slope, open air beneath, full sun.
  
• Yard: Various locations, all in full sun until about April, but some with morning shade or morning and mid-day shade thereafter.
  

See my Ecoroof Planting Plan for details on the ecoroof locations and polycultures.

Season conditions

Portland had an unusally wet and cool spring and early summer. This likely benefited the ecoroof plantings by providing low heat stress and enough moisture despite the thin soil and exposed conditions. Meanwhile, the yard plantings suffered from leaf rust and root rot (more details below.)

Uncontrolled variables

I planted garlic cloves 8-12" apart from each other, in various polycultures. I used a wider spacing than the usual 4-6" because I thought the thin ecoroof medium might not provide enough water and nutrients, especially with other polyculture plants mixed in. I created and planted the ecoroofs last fall, so they had few weeds and very young polyculture members. Engrossed in our house project, we did no weeding in the yard, so those plants had to cope with competition from many weeds as well as from nearby established plants, including overstory trees.

As noted above under "Test locations", some of the yard garlic varieties experienced varying degrees of shade from about April onwards.

Much of the yard garlic was planted in spots which have grown garlic in previous years (ie, no crop rotation). The yard garlic all got hit with leaf rust (super common around Portland this year), and some got root rot. The ecoroof garlic did not get either disease. I don't know that the leaf rust harmed the garlic all that much, but the root rot made many plants unusable. I discarded these bulbs from the figures, but some of the bulbs counted may have suffered partial damage.

Several of the garlic varieties I planted in the yard came from first year purchased seed bulbs, which means that I planted many small cloves. We had already grown out almost all the ecoroof varieties for at least one year prior, so we were able to select only the largest cloves for planting there.

I planted the ecoroofs first, and the yard a little later. This meant the ecoroofs had a week or two head start. More importantly, I wound up using the largest cloves on the ecoroofs since I popped cloves for planting as I went. The yard plantings got the smaller, left over cloves.

Expectations

I expected soil depth (and thus nutrient and water availability) would determine yields. So I expected garlic in the yard to give the greatest yield, followed by the front porch ecoroof, with the sunspace yielding the least. I didn't expect the condition of seasonal shade in some of the spots in the yard to have too large an effect. I expected the interplanting of garlic with other polyculture crops not to affect the garlic too much, since for most of its growing season the garlic has access to full sun, only suffering from some competition starting in May or June.

Harvests

Method

When I harvested bulbs this summer, I let the entire stalks air dry for about two weeks in the shade of our front porch.  Then I trimmed off the stalk and most of the root, and for each variety and location recorded the number of bulbs harvested and the total weight, to give an idea of weight per bulb. This allows comparisons of the yield in different conditions.

Data

Variety	Location	# bulbs	Weight (oz)	Weight/bulb	Notes
German Porcelain	Sunspace	24	22.5	.938
German Porcelain	Porch	18	20.25	1.125
German Porcelain	Yard	6	5	.833	Morning shade
Polish Jenn	Sunspace	18	32.25	1.792
Polish Jenn	Porch	13	16.25	1.25
Polish Jenn	Yard	9	8.25	.917	Morning shade
unknown #1	Porch	6	9.5	1.582
unknown #2	Sunspace	29	55	1.897	Minor morning shade
unknown #2	Front porch	15	24	1.6
Italian Late	Yard	24	9.5	.396	1st year seed cloves, heavy competition
Mild French Silverskin	Front porch	17	9.25	.544	1st year seed cloves
Mild French Silverskin	Yard	17	8.25	.485	1st year seed cloves, heavy competition
Nootka	Yard	12	6.25	.521	1st year seed cloves, heavy shade from hazel
Musik	Yard	11	12	1.091	1st year seed cloves?, only light competition
Appalachian Red	Yard	14	13	.929	1st year seed cloves, only light competition
Inchelium Red	Yard	21	13	.619	1st year seed cloves, fair amount of overstory shade
Spanish Roja	Yard	8	5	.625	1st year seed cloves, fair amount of overstory shade. May not have found all bulbs (numbers here reflect the 8 bulbs I did find.)
Elephant garlic	Sunspace	8	32.25	4.031
Elephant garlic	Porch	16	46	2.875	May have planted smaller cloves
Holland Red shallot	Sunspace	7	19	2.714	1st year seed cloves
Holland Red shallot	Porch	7	12.75	1.821	1 or 2 duds not counted. 1st year seed cloves
Holland Red shallot	Yard	4	3.5	.875	1 planted bulb vanished, not counted. 1st year seed cloves
Dutch Yellow shallot	Porch	11	18	1.636	1 or 2 duds not counted. 1st year seed cloves
Dutch Yellow shallot	Yard				Entire planting of 8 bulbs vanished (perhaps so runty that I just couldn't find them to dig them up? Hopefully they'll resprout this fall.) 1st year seed cloves
Variety	Location	# bulbs	Weight (oz)	Weight/bulb	Notes

Scapes

I harvested scapes from nearly all the garlic plants. I didn't track which varieties yielded what scape weights, or how many plants provided them, but here's the basic harvest info. I estimated the number of scapes based on number of bulbs harvested (from table above); I know I missed some scapes from the yard so I've adjusted that number down slightly. Also, I have a sense that not all of the varieties made scapes, so these numbers may be off by quite a bit in terms of weight per scape.

Location	# scapes	Weight (oz)	Weight/scape
Yard	106	21.25	.2
Ecoroofs	163	72	.442

Analysis

Garlic

Locations yielded inversely to my expectations: the yard yielded the least, the porch roof in the middle, and the sunspace the most. I attribute the low yard yields to the increased competition and disease problems mentioned above, especially since the plantings with the heaviest competition do seem to have yielded the lowest amount (though varietal difference could also affect this comparison.)

A friend just reminded me that garlic doesn't like hard soil, which characterises much of our yard soil. So that could also account for the reduced size of the yard garlic compared to the garlic growing in the very light-weight, loose ecoroof soil.

As I recall, all the sunspace growth (garlic and other plants) got off to an earlier start than on the porch roof. I now suspect that the heat from the sunspace room, despite about 14" of ceiling insulation and a 1" air gap, provides enough extra warmth to the ecoroof above to greatly improve plant growth. Alternatively or in conjunction, the south slope of that roof vs the north slope of the front porch roof may create enough of a microclimate difference to account for the improved yields.

I don't know why the German Porcelain garlic performed better on the Porch than on the Sunspace roof, in contrast to the other porch vs sunspace comparisons. Also interesting to note that the morning-shaded yard planting of this variety yielded only 10% less than the sunspace planting. Similarly, the yard planting of Mild French Silverskin amongst heavy competition came within 10% of the yield of the sunspace planting. Other varieties had much larger variance of yard vs ecoroof plantings.

Shallots

The shallots disappointed me, both on the ecoroofs and in the yard. Garlic wants its water to taper off in early summer, which is what makes it so well adapted to our climate of wet winter and dry summer; I had thought shallots share this preference. But looking over the literature, it seems shallots need water in the summer for best production; I provided them none. I want to keep the ecoroof largely irrigation free, so the shallots don't make sense there; in the future I'll plant them only in the yard, in easily irrigated areas.

Future Research

I feel very happy with garlic yields from the ecoroofs, so I don't see a need to grow any in the yard. We'll reserve the yard for more intensively managed crops, especially those benefiting from irrigation. That said, if we were staying here (instead of moving to Hawaii in a few months) and inclined to try the experiment again with better controls, I would:

• Pre-pop cloves and allocate roughly equal sizes to the different planting patches.
  
• Weed out the non polyculture plants.
  
• Crop-rotate the yard patches, especially where they suffered root rot.
  
• Plant yard and ecoroof garlic at the same time.
  
• Plant yard test plots in full sun to match the ecoroof conditions.
  
• Record scape harvests by variety and location to evaluate the full yield.
  
• Use cloves from bulbs grown out for at least a year, to give us the opportunity to plant only the largest cloves of each variety. This would allow better comparison across varieties.
  

We would still have the variable of different polyculture companions in different patches, but otherwise the extraneous conditions would be much more uniform.

Ecoroof Grant Report

Here's the report I wrote for the City of Portland's Bureau of Environmental Services, which gave us a $5 per square foot grant to implement our ecoroofs. You can also download a PDF (1 MB) of this report.

Update: addendum to the original report as a blog post or as a small PDF download.

Introduction

Project Summary

We implemented four ecoroofs on our residence at 4510 NE Going St, covering a total of 1000 square feet with ecoroof soil mixes sourced from Philips Soil Products in depths ranging from 3.5" to 8". We implemented and planted two in October 2010, and two in June 2011. We have another 660 square feet of house roof we deemed too difficult to beef up adequately to support an ecoroof. We roofed this area in metal, and it all drains onto the sunspace, front porch, and carport roofs.

About Us

Tulsey Latoski and Norris Thomlinson have experimented at this site since 2006 practicing sustainable, low-work food production via a food forest, perennial vegetable garden, and chickens and bees.

Read more about our projects in general at http://farmerscrub.blogspot.com

Read ecoroof-specific blog posts at http://farmerscrub.blogspot.com/search/label/Ecoroof

View food harvest logs from our ecoroofs at http://discountpermaculture.com/cgi-bin/harvest.py?ecoroof=1

Email us at norristh@gmail.com

Design Goals

• Food production - We planned the ecoroofs for production of food crops either naturally adapted to our seasonal rains, or drought tolerant to make it through the summer.
  
• Reasonably low maintenance - We hope for minimum irrigation requirements, no more often than once every week or two. Once the perennial plants have fully established they shouldn't require much weeding.
  
• Human hang-out areas - We included space for humans to spend time eating, reading, or watching the ecoroof or the rest of the neighborhood below.
  
• Bird & insect habitat - Our food producing, perennial plants provide a diversity of flowers for insects through several seasons, and various seeds for birds to eat.
  
• Potential rabbit or chicken fodder - We envision rabbits potentially grazing on the roofs with human supervision. We planted a few plants which can either serve as human food or be cut and dropped to the chickens below.
  

Four Roofs - Details

Sunspace

392 ft² (13' 3" x 29' 7"): A newly expanded room whose roof we rebuilt from scratch. This roof slopes south with 1/12 pitch, and we constructed it with an ecoroof in mind. The west end receives full sun year round; the east end receives dappled morning shade from black locust trees from late spring through mid fall. It holds 5.5" of intensive B-4 soil mix.

~290 ft² of metal roof drains into this roof, evenly distributed along a ~28' line, depositing into the upper end of the ecoroof.

Since we have the quickest and easiest access from our kitchen to this roof, we planned it as our zone of most frequent harvest, concentrating leaf and flower crops here for frequent picking. The central 2' wide path extending the length of the roof doubles as a sitting area. The south, lower end of the roof overlooks the back yard, where our chickens free range, allowing for possible harvest and dropping of fodder to the chickens below. Rabbits may eventually range here, but they would require a ramp to get to it from their likely dwelling area on the garage roof.

Front Porch

136.5 ft² (7' 3" x 18' 10"): The front porch roof slopes north with about 1/12 pitch. It receives full sun year round. It holds 8" of intensive B-4 soil mix.

To access this roof, we have to walk from the sunspace roof up and over 20' of metal roof, so we planned this roof for less frequently harvested crops such as root crops, seeds, and berries.

~265 ft² of metal roof drains into this roof, with about 2/3 of that evenly distributed along a ~19' line dropping water from above into the upper end of the ecoroof. The other 1/3 coming into the ecoroof meets the soil perpendicular to the slope, allowing very little infiltration; this water mostly runs straight down the side of the soil to a drainage pipe directing it to the gutter.

Garage

245.3 ft² (11' 6" x 21' 4"): The garage roof slopes south with about 1.5/12 pitch. It receives afternoon shade from the house and from late spring through mid fall much of the roof receives dappled to heavy shade the rest of the day from black locust trees. It holds an average of 1.5" of extensive-E soil mix, but we created mounds of soil 3 - 3.5" high in between paths and areas of no soil.

We have a hang-out area for three or four people to gather and sit together in the sun, plus the path lower in the roof in the shade of the locusts allows one person to sit. As with the sunspace, the south end of this roof overlooks the chickens and could be used to grow fodder plants, though the thin soil depth limits the possibilities.

Carport

227.2 ft² (11' 9" x 19' 4"): The carport roof slopes east with about 1/12 pitch. It adjoins the garage roof. It receives afternoon shade from the house. ~85 square feet of metal roof drops its water into the upper edge of this roof, with about 75% dropping into a single spot.

Two paths run the length of the roof, allowing for sitting in the sun or during the afternoon in the shade of the house. It holds an average of 1.5" of extensive-E soil mix, but we created mounds of soil 3 - 3.5" high in between paths and areas of no soil. The thin soil depth and mostly full sun exposure doesn't allow for much more than succulents and Alliums.

Structure & Layers

Structural Engineering

We worked with Ken Safe and Jeff Hartman at Miller Consulting Engineers to determine the necessary structural modifications to support a minimum additional ecoroof weight of 35 pounds per square foot (psf), allowing 5.5" of intensive soil mix:

Sunspace

We had already built the sunspace with 2x12 joists on 16" centers, spanning ~12', sheathed with 7/8" tongue & groove OSB. The north wall of the sunspace is a standard 2x4 stud wall, with a 2x12 ledger attached with lag bolts to carry the joists. The south wall is a window wall, with multiple windows 34" wide with 2x6 studs between them on 3' centers. A 6x8 header spans the windows and rests on 6x6 posts (one 9' and one 12' span between posts).

Miller determined that the 2x6 studs between the windows were too weak to handle the load from the 6x8 header, and the header couldn't make the full 9' and 12' spans on its own. They recommended the retrofit of adding a 2x6 LVL to both the inside and outside face of the header to stiffen it up. They also had us add SDS screws to attach the 2x12 ledger to the house wall, as the existing lag screws weren't strong enough. Because the window wall had too few areas of plywood sheathing to provide adequate shear strength, they had us add plywood to the interior north wall of the room, calculating that the shear load could be transferred via the OSB roof sheathing to that interior wall.

Front porch

Our porch roof had existing 2x6 joists on 16" centers, spanning 67", sheathed with 1/2" plywood. One end of the joists hung from a 2x6 ledger nailed to the house studs; the other end rested on a 4x6 beam supported by 4x4 posts. Miller determined that we needed to use a 4x12 beam instead of the 4x6, and 4x6 posts set in poured concrete pads instead of the 4x4s on pre-cast pier blocks. They also had us add SDS screws to attach the 2x6 ledger to the house wall. These changes permitted 50 psf.

Garage

Our garage roof has 2x6 joists on 24" centers spanning 10' 1", sheathed with 1/2" plywood. One end of each joist hangs from a 2x6 ledger lag bolted to the house; the other end rests on a 2x4 wall. Miller determined we would need one extra joist between each existing set for a final spacing of 12" on center, and we would need to strengthen the 2x4 wall.

Carport

Our carport roof has 2x6 joists on 24" centers spanning 11' 2", sheathed with 1/2" plywood. One end of each joist hangs from a 2x6 ledger lag bolted to the house; the other end rests on a 4x6 beam support by 4x4 posts. Miller determined that we needed to add two joists between each existing set for a final spacing of 8" on center, and do something to strengthen the 4x6 beam, such as adding metal C-beams. The 2x6 ledger against the house should have SDS screws added to attach to the house studs.

Scale-Down of Garage & Carport

We originally planned to implement the garage and carport roofs similar to the sunspace and front porch, with at least 5.5" of intensive soil mix to support food crops. However, these two roofs were built right up to the property line in the past, so to put ecoroofs requiring permits on these structures would have triggered requirements to bring various aspects up to code. We didn't want to deal with that, so we decided instead to implement very light ecoroofs of 30% of the allowed dead load value. Therefore, we did not add any joists or strengthen the beams for these roofs.

Layers

From bottom to top, the ecoroof layers consist of:

• Sheathing (1/2" plywood on all roofs except the sunspace with its 7/8" OSB)
  
• Feltex (light-weight substitute for tar paper)
  
• EPDM pond liner (45 mil Firestone Pondgard. We purchased sheets large enough to fit onto each roof without having to join multiple pieces together, so as to avoid potential leak spots.)
  
• Rotting wood (on sunspace and front porch roofs, to act as a physical dam slowing water down as it works down the roof, and to hold and store water and nutrients. Though the wood was already rotting and soft, we placed a thin layer of soil mix under the wood as an extra precaution to protect the pond liner.)
  
• Soil mix (Intensive on sunspace & front porch; extensive on garage & carport)
  

We figured that the roofs had sufficient slope (1 or 1.5 in 12) to move water via gravity through the soil mix, so we didn't include a separate drainage layer.

We created "raised beds" by using 2x6 and 2x8 boards around the edges of the roofs, running the pond liner up and over before capping the boards with metal rake edge protecting the edge boards and the sheathing, extending down at least 2" into the fascia boards attached under the sheathing. We secured the edge boards with 4"x4" right angle brackets, and placed scrap pond liner pieces or foam padding over the exposed metal to prevent the main pond liner layer from being damaged by the brackets.

Overflow

The front porch roof already had a gutter attached, so we worked with that for our overflow drainage. We lifted the lower "raised bed" edge board an inch off the surface of the decking, then cut slits in the pond liner to allow water to run under the board and into the gutter. We placed filter fabric all along the slit with a layer of river rock to retain soil.

For the other three roofs, we cut holes at the bottom edge of the roof through the decking, large enough to allow a 1.5" diameter PVC or ABS pipe to fit through. We cut the pond liner in an "X" pattern over the drainpipe, folded the flaps down into the pipe, and secured and caulked it with P&L Roof & Flashing Sealant. (For the garage & carport roofs we inserted a plastic ring to help hold the flaps against the inner wall of the pipe.) We used one hole each for the garage and carport roofs, and two holes for the sunspace roof.

Over each drainage hole, we placed a ~10" diameter coffee can with holes drilled or cut out all around the sides of the can. We cut one hole in the bottom of the can to match the hole cut through the pond liner. We wrapped each can with filter fabric then a ring of river rock to minimize loss of soil, and caulked the bottom of each can to the pond liner to secure it and prevent soil from getting under the can. We painted each can with rustoleum.

The excess water from the roofs drains to different places:

• Sunspace: waterfalls into three bath tub ponds, which then overflow away from the house
  
• Front porch: waterfalls into a large pond constructed of the scrap pond liner pieces left over from the four ecoroofs
  
• Garage and Carport: trees and shrubs near their respective downspouts
  

Plants

Sunspace & Front Porch Planting Plan

The deep soil of the sunspace and front porch roofs supports a relatively broad palette of plant species, and hopefully allows for productive cropping. We designed these roof plantings for polycultures of edible plants providing nearly 100% soil coverage throughout the year. Mostly we aimed for each patch to include an evergreen ground cover with evergreen or deciduous plants rising above.

For ground covers, we planted Arctostaphylos uva-ursi, Fragaria chiloensis, Rubus calycinoides, Viola odorata, Campanula portenschlagiana, C. poscharskyana, C. cochlearifolia, Gaultheria shallon, G. procumbens, Vaccinium angustifolium, V. vitis-idaea, Valerianella locusta, and Sedum telephium. For taller plants, we planted many Allium species including garlic and elephant garlic, Astragalus canadensis, Linum perenne, Hemerocallis sp, Agastache foeniculum, Asphodeline lutea, Chenopodium bonus-henricus, Sedum spectabile, Anthriscus cerefolium, Papaver somniferum, Oenothera biennis, several ephemeral bulbs in the Camassia, Triteleia, Brodiaea, and Erythronium species, and a few miscellaneous others. See our Ecoroof Final Planting Plan blog post for full details.

Carport & Garage General Plan

We didn't design the carport & garage roofs in as much detail, since we only had about 3.5" of soil depth to work with. We obtained numerous cuttings of Sedums and other succulents, mostly of unknown species from similarly thin-soiled, dry conditions. We also planted several Allium cernuum plants, one Fragaria chiloensis, a large Origanum vulgare, and a large unknown species of Thymus. In areas of the garage roof which receive heavy summer shade from the black locust trees, we planted Viola odorata and Campanula glomerata, since the protection from the sun may allow a wider diversity of plants to grow in that area despite the thin soil.

Mid-summer report

For an ongoing record of harvests from the ecoroofs, visit http://discountpermaculture.com/cgi-bin/harvest.py?ecoroof=1

Sunspace & Front Porch

Our one plant of Vaccinium moupinense died within a month of being planted. Our seeds of Lepidium peruvianum (old seed), Valerianella locusta, and Papaver somniferum never germinated. Otherwise, the plants on the sunspace and front porch, planted in October 2010, survived the winter and now flourish to a greater or lesser extent. The wet spring and summer this year have sustained growth with no irrigation on our part except for a few recently added plants, and occasional spot watering of some of our more valued experiments (Vaccinium angustifolium, V. vitis-idaea, Gaultheria shallon, G. procumbens, Chenopodium bonus-henricus, Akebia, and Astragalus canadensis).

The Fragaria chiloensis has impressed us with its rapid growth and precocious berry production; this species may make sense as the primary ground cover, since it stays evergreen, grows low, fills in gaps between taller plants very quickly, and tastes delicious! Large swaths of the Arctostaphylos uva-ursi died off following its transplantation from our yard below, but the portions that survived have made a few berries. Unfortunately, the berries of this species don't taste very exciting so it makes an inferior ground cover in our food-focused system. The Rubus calycinoides is establishing fairly slowly, though a few plants have produced flowers. The Vaccinium angustifolium is producing a few berries.

The garlic and elephant garlic seem to have done very well, producing numerous scapes followed by reasonably sized bulbs. We haven't weighed them all yet, but it looks like a very good yield. The other Alliums are establishing fairly well, but with much less vigor so far.

The Chenopodium bonus-henricus has produced a tiny amount of seed; we'll need to wait until next year to assess the production potential of established, mature plants. The Linum perenne made numerous flowers but only a handful across all the plants set seed; we're waiting anxiously to evaluate convenience of seed harvest and their taste. We're disappointed that the Papaver somniferum didn't germinate, as we would have enjoyed that as a seed crop. We have one Oenothera biennis plant flowering profusely, which should result in a reasonable number of seeds for ourselves or for the chickens.

Hemerocallis (daylily) is proving itself very tough, already producing numerous flowers for harvest.

Many other plants have flowered over the last two months, providing an ongoing diversity of blooms and making the roofs pleasant hang-out spaces and valuable for foraging insects.

Carport & Garage

We didn't plant the carport and garage roofs until late June 2011. A month later the cuttings and plants seem to be establishing well.

Implementation

We found it fairly straight forward to implement everything. For each roof, once we had the structural supports in place as designed by our structural engineer, we removed all the old asphalt roofing, tar paper, and roofing nails. We swept up all the dirt and debris to create a clean surface. In places with more than 1/8" gap between plywood we added shims so the pond liner wouldn't get stretched down into the crevice.

Once we had the plywood surface cleaned up, we laid the feltex on the decking in the same manner as tar paper. Then we placed our pond liner, running it under the flashings of the roofs above (sunspace and front porch) or up the wall of the house (garage and carport). We worked it up and over the "raised bed" edge boards, and cut off the excess. We adjusted the liner to minimize any bubbles in the middle of the roof, and folded the extra material at the corners.

The hardest part of placing the liner was dealing with the wood stove chimney projecting through the sunspace roof. We cut an oval hole about 2/3 the size of the chimney flashing, and worked the pond liner down over the chimney, making small cuts as needed to get the pond liner down to the roof. We had to make sure the pond liner stayed 2" away from the actual chimney, so we could only bring it up the flashing to that point. It proved difficult to cut the hole in exactly the right place, so we wound up with a slit in the pond liner extending upslope from the chimney for a few inches. We protected that by adding scrap pieces of pond liner, caulked to the chimney flashing underneath the storm collar and to the main layer of pond liner. To minimize water approaching from upslope, we placed two pieces of plastic to divert water to either side of the chimney. (We also initially placed a ring of drainage pipe and river rock around the chimney, but removed them later when we suspected that rainfall was splashing off those and getting under the storm collar.)

Next we placed the rotting wood for the sunspace & front porch, then soil for all the roofs. And finally, of course, we planted the plants!

Maintenance

Irrigation

Since we planted the sunspace & front porch roofs last October, and have had a wet spring with rains extending into June, as of July 12th we've only watered a few spring-planted additions and (perhaps unnecessarily) some of our more valued experimental plants (see "Plants" section above for details.) Since we completed the carport & garage plantings at the end of June, we expect to water two or three times a week to allow establishment.

The metal roofs condense some water during humid summer nights. We don't know yet whether that will provide any meaningful moisture input, but we hope that the plants at the upper edges of the sunspace and front porch roofs will benefit.

We expect to provide occasional (perhaps once a week) irrigation in future summers to maximize crop production, though certainly we have the option to not irrigate and just accept whatever harvests are possible.

Harvests

Most of the future maintenance should be simply harvesting greens & flowers two or three times a week, plus seasonal harvest of root crops like garlic, camassia, and yellow asphodel.

Further experimentation

We'll adjust the crops planted based on how well they perform. If new plants suggest themselves as good candidates, we'll try adding them.

Weeding

Hopefully most unwanted plants will be excluded by the establishment of a solid canopy of desired plants. After that, we just have to keep those desired plants in balance, which may mean rearranging some polycultures or selectively harvesting greens of certain plants more heavily to set them back.

Fertilization

The sunspace and front porch roofs will require ongoing fertilization to replenish nutrients taking during harvest. We can easily accomplish this by occasional application of urine during harvest trips.

Lessons Learned

Early loss of silt

The runoff water from the sunspace and front porch roofs obviously carried a lot of silt for at least two weeks after the beginning of the fall rains. Perhaps the ideal time to install soil and plant would be mid spring, so that plant roots could grow quickly while the soil was still moist, but without heavy enough rains to carry off so much silt and presumably fertility.

Excess water flows

Due to the extra water coming from our existing metal roofs, we had two problem spots. On two occasions of the heaviest rainfall last winter, the water flowing onto the sunspace roof backed up enough to get past the flashing and into the interior wall of the house. We added two drainpipes, one towards each end of the ecoroof, buried and running under the path directly down the roof. The pipes are wrapped in filter fabric with the upper ends protruding past the upper end of the soil for water to easily enter. This now allows excess water to safely drain away.

On the front porch roof, moderate rains caused a stream of water to overflow the lower edge of the "side channel" where some of the metal house roof meets the edge of the ecoroof perpendicular to the ecoroof slope. We built up a higher "dam" with metal caulked to the existing edge, which now allows excess water to enter a drainpipe running from that spot towards the gutter. The picture on the left shows eroded soil piled up against the original, shallow edge at the far right.

Gutter vs Drainhole

We found integration with the front porch gutter to be more awkward than the drainholes we created for the other roofs. We made a mistake by not caulking the pond liner down to the feltex along the slit we cut for discharge into the gutter, so water initially wicked back upwards under the pond liner and leaked through nail holes in the sheathing until we corrected the problem. The gutter will require more ongoing maintenance to keep it free of leaves than will the drainholes with their small cans.

Surprising absorption of rainfall events

We've been impressed by how much of the rainfall the roofs can hold before discharging anything into the overflow, especially the sunspace & front porch which receive so much extra water from the rest of the house. We haven't made precise measurements and observations, but it seems that if the roofs dry out a bit, they can fully absorb at least a .25" rainfall.

Difficult to buy low-cost plants

We were disappointed to find that we couldn't source low-cost sedums or other ecoroof plants. The wholesalers with good prices apparently only sell to retailers, not directly to end users, even if you can meet the minimum bulk requirements. Luckily, we found friends who allowed us to take cuttings of their sedums.

Costs

With the help of friends, we did all the labor ourselves, so we only had to pay for construction materials, soil mix, plants, structural engineering, and the permit. We located used material as much as possible via the Rebuilding Center, craigslist, etc. Our total cost was about $5400:

• $700 - Structural engineering
  
• $94 - Permit
  
• $180 - Concrete (front porch pier pads)
  
• $129 - Dump fees for old roofing
  
• $1023 - Lumber - structural posts & beams, sheathing, edge boards, etc. (We would have bought some of this lumber anyway for the sunspace, but it wouldn't have needed to be so beefy had we not put the ecoroof on it.)
  
• $108 - Nails & fasteners
  
• $157 - Brackets (to attach edge boards)
  
• $403 - Rake edge to protect edge boards & match existing metal roofing theme
  
• $148 - Feltex (light-weight tar paper equivalent)
  
• $849 - Pond liner
  
• $692 - Soil mix
  
• $906 - Plants & seeds
  
• $15 - Drain pipe for water overflow
  

Perennial polyculture: New Designs

This is part three of a three part series on perennial polycultures:

1. Designs: a five year review
   
2. Species profiles
   
3. New designs
   

Introduction

Following the massive failure of our original polyculture designs (see part one), I spent some time this past winter utilizing my hard-won knowledge of our successful perennials to try again. I didn't design anything for greens, since we have more than enough already established and coexisting quite nicely. I focused instead on root crops, which have proved more difficult to just plant here and there for a few reasons (not all reasons apply to all root crops):

• Soil disturbance damages adjacent perennials or roots of woody plants
  
• I lose track of where I planted odd plants after they've gone dormant, so can't harvest the roots
  
• Roots (especially those starting from small tubers or seeds) get outcompeted by other perennials
  

In this post I'll present the polycultures we're trying this year. I'll also mention a few other ideas I've had but haven't tried to implement. Refer to part two of this series, species profiles, for individual plant characteristics, presented in roughly the same order in which they appear in polycultures in this post.

Polycultures

Implementing

Garlic & Skirret

Garlic & skirret in foreground volunteer burdock & more skirret in background

This bicrop makes use of different time niches with these two root crops. I planted garlic at about 9" between bulbs, with skirret between with 9" spacing to other skirrets and 4.5" to neighboring garlics. Garlic grows through the winter and has died down in early summer by the time skirret has gotten big enough to begin competing for light. Garlic bulbs should lift out easily without disturbing the skirret, and skirret's drought tolerance allows for non-irrigation of the garlic while the bulbs dry down.

This patch could be replanted in the same place year after year by harvesting all the skirret in September and October, then replanting garlic cloves and skirret crowns. Or move the garlic to a new patch and harvest the skirret as needed through the winter, replanting the skirret crowns into that new patch as they become available.

Skirret, Day Neutral Strawberry, & Oniony Thing

This patch combines the need to thin strawberry plants with the need to thoroughly dig up skirret roots. It works because you can leave skirret in the ground for two years before harvesting, and because we have day neutral strawberries which should be thinned in late fall or over the winter. (June bearing strawberries should be thinned after they bear their crop in mid summer). I planted four rows 15" apart in a 5' bed, with skirret and strawberries alternating in their rows every 8". (16" between strawberries, 16" between skirrets, 8" from a skirret to the closest strawberry.)

I planted some sort of evergreen oniony thing between the rows to have some winter growth of its edible leaves. Originally I planned for the ongoing disturbance of the skirret & strawberries to prevent the oniony thing from getting swamped out. But as of mid June, the oniony thing is dominating the area and I'm aggressively harvesting their leaves to open up space for the strawberry and skirret!

This fall I would harvest skirret from two of the four rows (rows 1 and 3), replanting skirret crown divisions after harvest. This will wipe out most or all of the strawberries in those two rows. Next year the strawberries left in the undisturbed rows 2 and 4 will recolonize rows 1 and 3, while the skirrets in rows 2 and 4 grow for a second year.

Next fall I would harvest the skirret in rows 2 and 4, wiping out those strawberries and replanting the skirret crowns. Then follow the same pattern in the future, harvesting two rows each year, such that each row is harvested every other year. This should keep the strawberries from crowding themselves out, as a natural byproduct of thoroughly digging the soil to harvest the skirret. I would adjust the size of the skirret crown divisions in future years to integrate well with the strawberry growth rate--smaller if the skirret is outcompeting the strawberries, or larger if the skirret is getting swamped.

Skirret, Oca, & Potato

This patch uses time niches to some effect, though it doesn't have any winter evergreens.

Oca and potatoes alternate in rows with 16" from one oca to the next potato, (32" from oca to oca and 32" from potato to potato.) I spaced two rows 30" apart in a 5' bed. I then planted one row of skirret halfway between the oca/potato rows, with skirret on 12" spacing within its row.

Skirret and potatoes grow vigorously early in the season, with oca putting on growth more slowly. We'll harvest potatoes July through September, with skirret still providing shade for the oca in the heat of the summer. With the cooler cloudier weather in September, the oca vegetation should quickly fill out to use up the space left behind by the potatoes. We'll dig all the oca tubers out after the first frost, and harvest skirret as needed through the winter. We can either reimplement the same polyculture in the same bed, or rotate it to other beds to prevent disease problems with the potatoes.

Oca, Asiatic Lily, & Yellow Asphodel

Confusing mess w/unplanned strawberry etc

Utilizes different time and height niches. These are planted in an understory wedge to the north of a young persimmon. At 6' tall the persimmon casts minor shade. Oca is planted on 30" centers with asphodel surrounding it on 10" centers. One lily is planted in the center of each oca "triangle". I don't have enough asphodel propagated yet, but eventually their density could be increased to about 6" between plants.

Asphodel grows from fall through winter til early summer, making its roots available for harvest while the oca is still small. The oca and asphodel provide ground cover for the lily, which grows above them. Harvest all oca after first frost, and harvest lilies as needed through the winter.

Lilies and asphodels can be harvested with fairly minor soil disturbance, so the main conflict might be the effects of oca harvest on the asphodel roots with their new-ish growth going into winter.

We planted this polyculture into an area somewhat invaded by strawberries, and with remnant camassia and weeds including dandelion & popweed. We may have trouble with the strawberries especially, since we don't have a strong ground cover or weed excluding element.

Yellow Asphodel, Good King Henry, & Violet

Utilizes height & time niches. Violet should be an evergreen (we're using Viola odorata) for permanent low ground cover and winter greens, with the yellow asphodel and good king henry (GKH) growing up through it. The GKH begins growing late in the spring, but the other two plants should help suppress early weeds, and the asphodel will then die down in summer for the GKH to fill out further. We should be able to harvest the asphodel roots in the summer with minimal disturbance to the GKH.

I planted GKH about 2' apart, and would eventually like to have asphodel at 6-8" spacing filling all the interior area. We don't have enough asphodel plants yet for full density, so they're more sporadic for now. The violets will fill in wherever they find gaps.

Jerusalem Artichoke, Mashua or Groundnut, & Chinese Artichoke or Creeping Bellflower

Jerusalem artichokes with small chinese artichoke underneath

This polyculture has a core structure but multiple possible plants to plug into the different niches. It mimics the well known three sisters guild of corn, beans and squash, which Eric Toensmeier has proposed morphing into the perennial guild of jerusalem artichoke, groundnut, and chinese artichoke. This polyculture makes use of above ground space niches, but not of time niches, since these root crops require heavy disturbance for harvest in fall through early spring. With the possible exception of the creeping bellflower, they should all benefit from the regular ground disturbance and loosening of the soil.

We're retaining jerusalem artichoke as the vertical element; we had an existing 100 square foot patch. However, we've never had much success growing ground nuts here, so we only planted 3 or 4 which survived from last year, instead mostly planting mashua on 3' centers as the vining element to climb the jerusalem artichokes. We can easily supply nitrogen via our urine so we don't require the leguminous groundnut for nitrogen fixation.

For the ground cover layer, we're trying about half a dozen fast-spreading chinese artichoke in half the patch, with creeping bellflower 1-2' apart as another vigorous, shade tolerant root crop in the rest of the area.

Our patch gave us about 100 pounds of jerusalem artichokes last year (1 pound per square foot). It makes sense to knock back the jerusalem artichoke production a bit in favor of more root diversity, and hopefully the total yield of roots will increase while we're at it.

Brief Mention

Oca & Tomatillo / Ground Cherry

Ocas & tomatillo at bottom tree collard and mashua at top not part of guild

Inspired by oca-testbed's oca & tomato bi-crops, I've planted 3 ocas, 2 annual ground cherries, and 2 tomatillos with 10" between each oca and its neighboring ground cherry or tomatillo (20" from one ground cherry or tomatillo to the next).

Squash & yacon

I planted some squash seeds at 6' centers and yacon halfway between at the 3' mark. The yacon should grow tall enough to hold its own by the time the squash reaches it, to share the space niche a bit. It may work somewhat as a time niche, too, as squash often dies back in early to mid fall with powdery mildew, while the yacon can keep growing until frosts kill it.

Not Implementing

Oca & squash

We created an accidental time niche bicrop a few years ago when a squash covered up some oca for most of the summer, but started dying back with powdery mildew in early fall, allowing the oca to explode in growth and fill out the space. We didn't get much of an oca yield--but I wasn't experienced enough at that time to pay close attention to frost and harvesting all the oca promptly. So maybe we got some roots but they rotted? Or maybe the squash didn't allow the oca to grow well enough to produce roots? I'd like to try this again with squash on 6' centers and two or three ocas at the 3' point in between. Or try combining it with the squash & yacon polyculture, with the squash and yacons spaced further apart to allow oca some breathing room between the larger plants. (See oca-testbed's polyculture mound of yacon, oca, and chinese artichoke.)

June bearing strawberry & summer root crop

I've tried to design a polyculture which combines digging some root crop with the need to thin June bearing strawberries in late summer, after they've finished cropping for the year. I've had a much harder time with this than with day neutral strawberries (see my polyculture with skirret above), since very few root crops can be harvested in the summertime after two years of growth to allow the alternating row harvest method. Strawberries fill out quite well by mid spring, creating a lot of competition for anything shorter than they are, limiting the ability to sow seeds or plant small divisions at the beginning of the growing season. Further, the root crop can't be allowed to outcompete the strawberries too badly -- we have some burdock in our patch, and we have to keep harvesting the huge leaves (we do eat the leaf stalks) or the strawberries get totally covered up!

Spring ephemeral bulbs such as Camassia, Triteleia, Brodiaea, or Erythronium might work for the row harvest method, especially if you establish a solid patch first, then add strawberries later. Or instead of harvesting a full row at at time, you could do a distributed harvest of the thickest clumps of bulbs, disturbing patches of strawberries here and there while eating the largest ephemeral bulbs and leaving the small ones behind to regrow quickly the following spring. Or try root crops whose seeds can germinate in the autumn, overwinter as a small plant, and grow quickly in spring: black salsify (Scorzonera hispanica) or dandelions for full row harvest after 1.5 years, or black salsify, dandelions, or parsnips for distributed patch harvest the summer after they've been sown.

Perennial polyculture species profiles

This is part two of a three part series on perennial polycultures:

1. Designs: a five year review
   
2. Species profiles
   
3. New designs
   

Introduction

In Perennial polyculture designs, I mentioned inadequate knowledge of plants as one barrier to successful implementation of my designs. We've now gained enough knowledge of a few perennial plants to try again. With this mouthful of a title, I give the relevant design characteristics of perennial vegetables we're trying in polycultures this year. Unless otherwise noted, I consider these plants primarily root crops, though some have secondary uses like edible flowers or leaves. By the way, for more information on many of these unusual root crops, including some polyculture experiments, see:

• Oca testbed - nice details on tomato & oca bicrops, plus lots more on oca and some on other roots
  
• Radix Root Crop Research and Ruminations - pioneering work with many roots I haven't tracked down or in some cases even heard of before
  
• Obligatory link to Plants for a Future database.
  

Species characteristics

Garlic (Allium sativum)

• Harvest time: July or August
  
• Harvest process: Lift all bulbs, which doesn't require much soil disturbance. Store in cool dark place.
  
• Planting process: Plant cloves in October or November, which doesn't disturb soil, but cloves shouldn't be disturbed by other digging after being planted.
  
• Generally doesn't require any watering, and in fact shouldn't receive water in July so the bulbs can dry out for long term storage.
  
• Vegetative growth: small amount of leaves over the winter, growing more actively in spring. Die back in July with the summer drought.
  

Skirret (Sium sisarum)

• Harvest time: October through April. Stores in the ground all winter.
  
• Harvest year: can harvest after one year of growth, or leave in the ground for multiple years for more and larger roots, which seem less prone to having a woody core.
  
• Harvest process: Dig large chunk of soil from around plant (up to 2.5' diameter with older plants), pull out crown. Cut off roots, optionally divide and replant crown. Can be difficult to find in late winter after stalks have rotted away.
  
• Drought & shade tolerant
  
• Vegetative growth: Appears mid-season (April), grows fairly quickly to 3-5' tall (depending on age of plant), and dies down in early fall (October). Dense, casting heavy shade.
  

Garden strawberry (Fragaria x ananassa)

• Use: berries
  
• Harvest time: summer through fall
  
• Best with full sun and adequate water through growing season.
  
• Benefits from thinning (following the annual harvest for June bearing varieties, and in the winter for day neutral varieties)
  
• Vegetative growth: semi evergreen to 1' high, spreading quickly from runners
  

Potato (Solanum tuberosum)

We haven't actually grown potatoes very much, but my understanding so far:

• Harvest time: June onwards. Can probably store in the ground through the winter?
  
• Harvest process: Seems to need a fairly thorough excavation of the soil, especially to find all the roots. We had many potatoes return this year from last year's plantings, so this seems to have potential as an overwintering perennial. Disease buildup normally demands crop rotation.
  
• Supposedly fairly drought and shade tolerant.
  
• Vegetative growth: Starts growing in late March or April. Reaches 3' wide? Yields supposed to improve with hilling up soil onto the lower stem.
  

Oca (Oxalis tuberosa)

• Harvest time: after the first light frost(s) kill the foliage, but before hard freezes damage the tubers, which often dwell close to the soil surface.
  
• Harvest process: Dig out all the roots, generally concentrated at the center, though some may form where foliage touches the soil. Store in cool dark place for the winter, replanting some tubers in spring. In mild climates, tubers missed at harvest time may resprout on their own in spring.
  
• Appreciates some shade during heat of the summer, but may not tolerate too heavy competition. We tried it as a ground cover amongst other plants one year, and they swamped it out with very little root yield.
  
• Vegetative growth: Leafs out in April or May, generally low growing to about 1', though can clamber up other plants if it needs to gain access to sunlight. Doesn't put on much growth until September, when cooler cloudier weather kicks in, at which time the foliage explodes to 3-4' wide.
  

Asiatic lily (Lilum sp)

• Harvest time: Late fall through early spring.
  
• Harvest method: Compact bulb, so fairly easy to harvest with minimal soil disturbance. Leave large offsets behind to regrow. Can be difficult to find in late winter after top stalks have rotted away.
  
• Like their feet in shade and top growth in sun, thus well suited to combination with a low ground cover.
  
• Vegetative growth: comes up in early to mid spring, grows to 3-4' tall, and dies down in fall.
  

Yellow asphodel (Asphodeline lutea)

• Harvest time: Can definitely harvest in the summer, and I think we can dig roots year round.
  
• Harvest process: Medium soil disturbance, concentrated around center of each plant. The plants make numerous offsets, and each plant has multiple thin roots. So you can harvest some entire plants and leave/replant others, or cut some of the roots off of each plant and replant them all for slower/less vigorous regrowth. Not sure yet of the best method.
  
• I think it prefers full sun, and probably doesn't need any irrigation.
  
• Vegetative growth: somewhat sparse, to about 1.5' tall on flowerless plants, or 3' tall on single flower spike. Doesn't seem to compete all that well with other plants, so may do best with a low growing ground cover for weed exclusion. From the Mediterranean, so well adapted to our summer drought by dying down in mid summer and coming back with fall rains, staying green through the winter.
  

Good King Henry (Chenopodium bonus-henricus)

• Uses: leaf crop (spinach substitute) and seed crop (used like quinoa, though smaller).
  
• Harvest time: leaves throughout season. Seeds over a period of about three months, July through September.
  
• Harvest process: seeds require periodic picking every week or two as different seed stalks ripen at different times.
  
• Somewhat shade & drought tolerant, though I assume for optimum seed production we should give it full sun and summer water.
  
• Vegetative growth: comes up in late spring, reaching about 1.5' tall and perhaps a bit wider. In our back yard where chickens roam, we have a fairly pure stand of GKH and it does fine. In our front yard, (because chickens aren't eliminating the other plants? or because the GKH hasn't dominated the root zone yet?) the GKH gets crowded out by the early spring growth of nipplewort (Lapsana communis), lemon balm (Melissa officinalis), and wood avens (Geum urbanum) and I've had to weed the bed this year. Like the yellow asphodel, would probably benefit from a low growing weed suppressing ground cover.
  

Jerusalem artichoke / Sunchoke (Helianthus tuberosus)

• Harvest time: October through April
  
• Harvest process: Major soil disturbance. Will always miss some roots so that it will regrow the next year. Can be difficult to find roots in late winter after stalks have rotted.
  
• Drought and shade tolerant
  
• Vegetative growth: appears mid spring, reaches 8+' tall. Dies off in late fall.
  

Mashua (Tropaeolum tuberosum)

• Harvest time: In theory, should harvest after the first light frost(s) kill the foliage, but before hard freezes damage the tubers. Roots seem much hardier than oca and yacon, though, such that they might store OK in the ground through the winter.
  
• Harvest process: Fairly thorough excavation to dig all roots, storing in cool dark place for the winter. We usually miss some of the roots so that it regrows the next year.
  
• Appreciates some shade during heat of the summer
  
• Vegetative growth: Vining to at least 10' tall, climbing other vegetation. Appears in mid spring and grows at a fairly steady rate until frosts.
  

Groundnut (Apios americana)

(c) 2004 Steve Baskauf

We haven't had much success with this plant, but we haven't totally given up on it yet..

• Harvest time: dormant season, late fall? through late spring?
  
• Harvest method: Extensive excavation required. Leave some tubers behind to regrow.
  
• Fixes nitrogen
  
• Vegetative growth: vining, scrambling up surrounding vegetation. In our climate, appears around June and disappears in September or October.
  

Chinese artichoke (Stachys affinis)

We've only grown these for one year, so I base this mostly on the literature:

• Harvest time: Dormant season (fall through early spring)
  
• Harvest process: Probably requires major soil disturbance, especially since I don't think dead plants leave woody stalks behind to mark their spots. Will regrow in spring from tubers you missed.
  
• Moderate moisture requirements?
  
• Vegetative growth: appears in early or mid spring, gets about 1' to 1.5' tall, runs quickly (mint family) and forms good ground cover. Not sure exactly when it dies down.
  

Creeping bellflower (Campanula rapunculoides)

• Harvest time: I think we can get usable roots year round.
  
• Harvest process: Fairly major soil disturbance. Need to dig towards the center of the clump to find usable roots. I suspect it will keep regrowing vigorously after each harvest with no need to deliberately leave roots behind.
  
• Very shade tolerant, and competes well with other vegetation.
  
• Vegetative growth: Leaves appear in early spring and make a good source of greens while others are somewhat scarce. Plant reaches about 3' tall and runs vigorously. I think that without irrigation it responds to our summer drought by going somewhat dormant, resuming growth in the fall before dying back for good over the winter.