Introduction to forest gardens

The forest garden is a kind of system that we very commonly use in permaculture projects. It mimics the ecological interactions of a forest, but we build it from elements that we choose for specific purposes. Almost always, these purposes include human consumption, and often they include animal forage, medicine, fuel and fiber. So once we have our list of needs, we cross-reference that with our knowledge of the site and that way we make our species selection. The eco-mimicry of forest gardens makes them extremely productive, resilient and low-maintenance systems. They take full advantage of the same ecological interactions that guilds use. If we leave an established forest garden without maintenance for a few years or decades, it will continue to produce well. If we put in a few days of maintenance a year, we can get more production out of it. It’s not a matter of more work, but of better-thought-out work.

A forest garden can be a backyard affair, or it can be a landscape-wide system.

The classic seven layers of a food forest

Too often, when people think of a forest, they forget that trees are not the only essential element.

A forest has not only trees, but also many other elements. In permaculture, we organize these elements into layers. This helps us fill every ecological niche. The classic layers are so:

1. Canopy trees
2. Understory trees
3. Shrubs
4. Herbaceous plants
5. Groundcovers
6. Bulbs/Tubers
7. Vines

Then there are several more layers, that might be there or not, depending on climate. Here I will put the layers that tend to be important specifically in temperate climates.

8. Lower Herbaceous layer
9. Fungi

We can fill each one of those layers with several different elements that provide us with the resources we require. So for a typical Russian climate:

• Good canopy trees include black locust, Siberian pine, sugar maple, edible chestnut, hickory, birch.
• Understory trees include pear, apple, peach, plum, sour cherry, sweet cherry, russian olive.
• Shrubs include Siberian pea shrub, currant, blackberry, raspberry, sea buckthorn, blueberry, haskap, goumi, goji.
• Top herbaceous layer plants include comfrey, kale, rhubarb, knotweed, perennial wheat, burdock, nettles, daylily, asparagus.
• Lower herbaceous layer plants include mayapple, ginseng, yarrow, plantain, mint, lemon balm, dandelion.
• Groundcovers include goutweed, strawberry, wild strawberry, clover, vetch.
• Bulbs and tubers include jerusalem artichokes, garlic, egyptian walking onion, gladiolus, daffodil, groundnut.
• Vines include grape, hardy kiwi, hops.
• Fungi include winecaps, champions, white mushrooms, lisichki, podberyozki.

After we make our plant choices, we design the positioning of the plants in relation to each other, the sun angles, the landscape and the pathways. If this is a zone 2 forest garden, it is more garden-like, with individual plants carefully placed individually. We plant a larger system (zone 3, zone 4) in a repeating pattern, with less nuance, less diversity and more straight lines. You work out what kind of forest garden and what guilds you’re going to put in, and spread it out across the landscape.

Establishment process

So that’s what a forest garden is, in description. It is another question how to establish one. There are several steps to this process. So let’s describe a typical establishment process in order, using the elements and methods described above. Let’s assume we are setting up a Zone 3 system.

Step 1: disturbance

The first is disturbance. We need to remove whatever system is already in place where we plan the forest garden, and we must do it in a way that facilitates the growth of the forest garden that we will put in. If you put in a swale (I will cover these later), the disturbed soil on the berm is ideal for planting into. Animals, such as pigs or chickens, can disturb an area and fertilize it at the same time.

If neither of these are options, you can cover the planting area with a double layer of cardboard, and put at least 10 centimeters of woodchips on top of the cardboard. Leave it for a year, and then plant straight through it, pulling the woodchips a few centimeters away from the stems of the young plants. In any case, when you plant you need to spread mulch in the planting area.

In our case, we will use chickens as a disturbance mothod. We temporarily fence the planting area, and hold a high-density chicken flock there for a week.

Then we move the chicken flock off to the next planting area.

Step 2: planting

Immediately after we move the chickens, we plant the planting area to all of the forest garden plants at the same time, excluding plants that require a forest environment to survive.

When you plant, you want 50% to 90% of the plants to be nitrogen fixers. That usually means plants in the bean family, but there are many plants from other families that also fulfill this function. Later we will cut down many of these plants, especially trees, as “sacrificial” trees and use them for mulch.

With every canopy and understory tree that is not a nitrogen fixer, we plant a sacrificial tree of the same layer to the southwest of it, a meter away. Take care to space the canopy trees far enough apart that some light still reaches the shrub layer. Raspberries yield best in 40% shade. We mulch the area with straw or woodchips, and plant a mix of annual temporary groundcovers, like buckwheat, sweet clover, amaranth and squash or melon. Squash is especially useful, because it generates so much biomass and shades the ground well. In the fall, we quickly chop down these groundcovers and drop them on the ground, and collect any useful harvests. We can use amaranth and buckwheat as supplemental winter chicken feed. The main goal of these annual groundcovers is simply to take up space, surpress weeds and start off the mulch creation process.

After the first year

By the second year, the clover and vetch should have taken up their positions.

By the third year, the strawberries and goutweed are starting to push out the clover and vetch, and the berries start yielding very well, especially the sea buckthorn. The nettles, daylilies and asparagus are yielding well, along with the herbs. Kale grows as a kind of encouraged weed. In the fall, you just grab the seedpods and rub them in your hands, scattering the seeds. This is the first year when you cut the sacrificial trees to about 1.5 meters tall. Do this every second year, in the fall, and drop the cuttings on the ground as a form of mulch. This feeds the soil.

By the fourth year, the berries are still yielding well, and the first fruits are coming in from the understory trees.

By the fifth year, most of the understory trees are yielding well and the production from the berry bushes is starting to decrease slightly. We can allow the chickens back into the system for about three days at a time. This can take the form of a cyclical movement of the chickens through different sections of the forest garden. At this point, the strawberries and goutweed have almost entirely excluded the clover and vetch from the forest garden.

By the tenth year, the sacrificial trees should be cut down all the way to the ground every year. By this point their job is done. The canopy trees should start to yield about this time. About this time, the plants that are dependent on a forest enviroment, like ginseng, can be introduced, as well as a variety of mushrooms, and there’s no reason why these can’t be very valuble mushrooms.

By the twentieth year, all the layers are yielding well. Some maintanence is occasionally needed to let some light into the lower layers, increasing the production. The ground under the trees is beautiful black soil.

By the fortieth year, some of the trees can be harvested for timber, and they are replaced by new plantings. The forest garden has reached climax. The chickens maintain the understory, eating pest larvae and fertilizing.

This has been an introduction to food forests.