Build a Backyard Edible Ecosystem

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Zach Loeks
Use a tarp to kill any grass or other plants before you set up the bed.

Fruits, vegetables, and flowers can transform neighborhoods into abundant, beautiful, healthy environments. If we plant fruit trees, berry bushes, and herbs, we can begin to form new food landscapes throughout our communities. The best way to start this process is by building a small edible ecosystem in your backyard that includes a simple compost system that will become the bed for your perennial food plants.

What’s an Edible Ecosystem?

An edible ecosystem is a planned garden that features diverse food plants that complement each other’s forms and functions, imitating the structure of a natural ecosystem. I create ecosystems that include a mix of three or more varieties of herbs, berries, and fruit trees, along with beneficial fungi, which all work together to produce an abundance of food. These miniature permaculture gardens also provide space to trial potential food plant guilds and propagate new plants to share with your community.

By starting small and trialing different combinations of perennial food species, you can learn what works well and then share that successful design with your neighbors. For instance, if a certain berry cultivar is delicious and works well with a ground cover of thyme, you can suggest that design to others in your area. You’ll also be able to turn your garden into a nursery source for propagating other sites in your yard and community.

Permaculture Gardens Mimic Nature

A well-designed edible ecosystem will offer improved yields and require less maintenance than a traditional food garden by mimicking the form and function of natural ecosystems. Form refers to the different canopy and root shapes and the plant sizes used — fruit trees, berry bushes, and ground covers have notably different forms. You can maximize water, nutrient, and sunlight use within your garden plot by layering diverse leaf and root profiles.

Function refers to plants with different — and complementary — life cycles. This is the premise behind companion planting in any environment. For instance, a larger fruit tree can shelter smaller plants from wind and heat; ground covers, such as thyme, can keep out weeds; herbs can confuse pests; and grapes can use another plant’s stems for a trellis. Some plants have coevolved to form symbiotic relationships, and some plants simply work well together in a planned ecosystem.

Compost Spot to Garden Plot

Pay attention to the useful waste materials available in your community, from home food compost and paper recycling to yard waste, bagged leaves, and downed twigs and branches. In combination with backyard soil, small straw bales, and bagged potting mix or compost, you can easily create an edible ecosystem in any 8-by-8-foot space. Use small square hay bales to form the borders of the garden, and fill the central space with layers of debris, compost, and topsoil. Woody debris will keep the composting layer aerobic by creating air space, while compost will provide nutrients for microorganisms. Recycled paper and dry yard waste will serve as mulch to prevent weeds from growing and to retain moisture for your edible perennials.

How to Construct an Edible Ecosystem

First, choose a site that’s accessible for yard work, has good drainage, and has enough space to grow a fruit tree that’ll mature at about 15 feet tall. The site can be in full sun or partial shade, but you’ll need to pay attention to light requirements when you select species to plant.

After you’ve chosen your site, you’ll need to kill the plants already growing there. The easiest way to do this is to lay down a 10-by-10-foot tarp (you can fold a large tarp to fit the space) and weight it with square straw bales. Leave the tarp and bales in place all summer to fry any grass and weeds underneath. Next, remove the bales and tarp, and place a layer of cardboard over the newly exposed soil to act as sheet mulch. If you want, you can skip the plastic stage and just cover the grass with a cardboard sheet mulch. Overlap the cardboard by at least 18 inches to ensure grass doesn’t grow into your edible ecosystem.

Next, use six of the square straw bales to form an 8-by-8-foot border for your edible ecosystem, and inoculate them with edible mushroom spores before other wild fungi can take hold. To inoculate them, cut into the straw with a root knife and insert your preferred mushroom spawn; you can use oyster or enokitake sawdust spawn. The best way to find varieties suited to your area is to talk with local gardeners, farmers, and nursery staff; alternatively, you can take a risk and try something local growers aren’t using yet. It might fail, or you might discover your new favorite edible fungus!

To prepare the bed for perennial food plants, fill the center with successive layers of woody debris, compost, leaves, and soil, until it’s full. To get started, scavenge woody debris and prune any hedges or trees you have, and layer this material on top of the cardboard. Add a mix of grass clippings and household compost to the heap on a weekly basis. Bagged compost or some soil from your yard can speed up the decomposition process. An occasional 5-gallon pail of manure or forest soil is a great source of beneficial microbes to jump-start the composting process.

Finally, top off the entire mound with topsoil or bagged compost, rake it smooth, and seed it with a mix of winter rye and red clover. This can be done in fall, and the cover crop roots will stabilize the mound over winter. You can let the plants grow as long as you want; if you leave the cover crop to grow until the following midsummer, you can then cover it with a piece of black plastic for 7 to 12 days to kill the plants and make an in-place mulch.

Sometime between filling your compost area and killing the cover crop, select the plants you want to grow in your edible ecosystem. I recommend choosing a small fruit tree, a berry cultivar, one or two herbs or edible flowers, one or two ground covers, and a fruiting vine. A local nursery can help you select species suited to your site, your climate, and your desires; small nurseries are often more familiar with which plants do well in a particular area, and can offer advice on new cultivars to try. Consider site drainage, hours of sun per day, and USDA Hardiness Zone as you make your choices. You could also reach out to a local permaculture designer for advice on how to maximize your garden’s productivity and resource use.

After planting in spring, you’ll need to mulch your ecosystem. If you grew a cover crop for in-place mulch, this next step may not be necessary — but it won’t hurt. Cover the surface between the plants with newspaper, and cover that with fine hardwood chips and more straw or leaves from your yard. The newspaper and mulch will suppress weeds until the plants are established, and will prevent unwanted volunteer plants from germinating. You can run a soaker hose between the plants to keep them moist while they establish themselves. Keep the soil moist, but not sodden.

By filling available garden space with edible plants of differing forms and functions, you’ll have created an ecosystem that will use resources, such as sunlight and water, more efficiently and produce food with less effort from you. The ground cover will spread between the other plants, which will offer shade and wind protection to each other as they grow. Nonaggressive vining plants can be supported by the fruit tree as a living trellis.

Spread the Wealth

These micro-ecosystems can be repeated many times in your yard or on a homestead. Just place nametags by each plant so you don’t forget the cultivar names and can document your successes. Your favorite plants can easily be shared with neighbors to begin to build an edible ecosystem neighborhood through the harvest and movement of suckers, scions, and seeds to other homeowners. In fact, this is necessary! Your plants will propagate themselves through seeds and suckers, and you’ll want to harvest the surplus and share it.

In an edible ecosystem, the diversity of plants work to shelter each other, capture sunlight, and create symbiotic relationships with each other, supported by the healthy soil you’ve nurtured below. Begone, stinky compost piles! A planned, biodiverse ecosystem will make immediate use of your waste to grow food as a beautiful landscape feature.

Remember to start right: Build a good compost bed, bring in some well-researched cultivars to mimic the natural layers of a woodland ecosystem, and do a good job mulching and watering for the first year. Then, just maintain the mulch layer and enjoy your harvest!

Edible Ecosystem Example

Here’s an example of an edible ecosystem designed for Zone 4, my hardiness zone. Some of the food plants I chose required two individuals for proper pollination. The overall number and types of plants, however, follow the pattern of a woodland ecosystem.

Fruit tree: 1 ‘Northbrite’ European pear

Woody bushes: 1 black raspberry and 2 Haskap berries

Herbs: 1 mint and 2 bee balm plants

Ground covers: 24 thyme and 24 strawberry plants

Vines: 1 ‘Somerset’ grape or hardy kiwi

Edible fungi: One 5-pound bag of oyster or enokitake sawdust spawn

The pear should be planted in the middle of the edible ecosystem, with a rodent guard around its main stem until the trunk establishes a thick bark. The berries need to be planted in the corners of the planting area to have room to grow and access to sunlight. Plant the herbs along whichever edges suit their sun requirements. Mint tolerates shade, so it should go along the north side of the ecosystem, and bee balm should be planted along the sunny south side.

The ground covers should be planted in a similar fashion, according to their sun and shade tolerance. Thyme can prosper in partial shade, so it should be planted in a grid every 6 to 12 inches on the northern half of the bed, around the pear, berries, and mint. The strawberries need more sun, so they should be planted on the sunny southern half of the bed, again distributed between the berries and bee balm. The grape should be planted on the south side of the pear tree and trained up its trunk. The vine will protect the trunk from sun scald on that side, and will use the tree as a trellis. The mushroom spawn should be inserted into the hay long before the other plants go in, and will spread throughout the bales to produce edible mushrooms and hasten the decomposition process.

Zach Loeks runs a permaculture farm in the Ottawa Valley, Ontario. He is a permaculture educator and the author of The Permaculture Market Garden. Find him on Facebook, Instagram, and YouTube @zachloeks.