Forests in nature are resilient, diverse, self-regulating ecosystems. They provide all the nutritional needs of their residents – birds, mammals, reptiles, insects, microorganisms, etc. A forest garden, sometimes called a food forest, does the same for people, providing food, shade, wildlife, and an outdoor place to enjoy. A forest garden is a cultivated, edible, and diverse ecosystem that mimics a natural forest in form and function but is usually much smaller, from the size of a small urban backyard to a few acres of rural land.
Natural forests can provide food for people, too, but foraging for food in them usually isn’t practical or sustainable. Rather than foraging in natural forests, we can cultivate food forests in our own backyards and community gardens. These cultivated forests produce fruits, nuts, berries, greens, herbs, and vegetables—whatever varieties that are suited to the local climate and that we choose to grow for our own nutritional needs and culinary desires.
Benefits of a Forest Garden
There are so many benefits to growing a food forest, I don’t know why everyone who has a backyard isn’t growing one of their own or at least a couple of fruit tree guilds. Food from your forest garden is organic, fresh, and as local as it gets.
Of course, which species do well in a food forest depends on the local climate and site conditions. But almost any climate can support a food forest with the right species selection. Dry climates will need a source of irrigation water to sustain a forest garden.
The Seven Layers of a Forest Garden
If you look at a natural forest, you’ll see multiple species coexisting in a small space. Each type of plant (tree, shrub, ground cover, etc.) fills its own niche or layer in the forest.
A food forest emulates this layering that occurs in nature. This not only provides more opportunities for growing food in a small area, but it also forms a support system for the plants. When plants support each other, they require fewer inputs from the gardener.
Specific species to include in each layer varies depending on climate and personal preference, but in my list below, I’ll include some examples of plants that might occupy each layer in a temperate climate.
Canopy Layer
Also called the overstory, this is the top layer of a food forest. It’s made up of relatively large trees that form the large-scale structure of a food forest. These trees provide wildlife habitat and shelter to protect the other layers while still allowing sunlight through or beneath the canopy. Overstory trees should be widely spaced enough to allow plenty of sunlight into the layers below.
Examples of canopy trees
- Nuts: hazelnuts, chestnuts, hickory
- Fruits: persimmon, mulberry, standard or semi-dwarf apple, pear, cherry, plum
- Nitrogen-fixing: alder, black locust, Siberian pea tree
Sub-Canopy Layer
This is the second-to-top layer, although in smaller food forests with limited space, it’s often the top layer. Small fruit and nut-bearing trees or grafted varieties on dwarf or semi-dwarf rootstock occupy the sub-canopy. These trees should be pruned to have an open canopy that lets light into the lower layers.
Examples of sub-canopy trees
Dwarf and semi-dwarf fruit trees such as
- apple
- pear
- cherry
- plum
- peach
- and figs, to name just a few
Shrub Layer
Between and beneath the sub-canopy is the shrub layer, containing thicketting plants up to ten feet tall. The shrub layer contains berry bushes, fruiting or nut-bearing shrubs, nitrogen-fixing shrubs, and other beneficial shrubs. Some overlap exists between the sub-canopy and shrub layers. Many plants in this category can grow as shrubs or small trees depending on how they are pruned.
Examples of shrub layer plants
- gooseberry
- currant
- serviceberry
- chokecherry
- wild plum
- blackberry
- sea buckthorn
Herbaceous Layer
The Herbaceous layer fills in the smaller spaces between trees and shrubs. It contains non-woody annuals and perennials that often die back or can be cut back to mulch and replenish the soil each year. It’s full of medicinal and culinary herbs, flowering pollinator attractors, and other beneficial herbaceous plants.
Examples of herbaceous layer plants
- comfrey
- sunflowers
- rhubarb
- asparagus
- calendula
- chamomile
- fennel
- oregano
- chives
- bee balm
- anise hyssop
Ground Cover Layer
These low-lying, horizontally spreading plants fill in the remaining ground area, providing soil cover, weed suppression, green mulch, food, animal fodder, and other functions. It sometimes dies back over the winter, adding biomass and nutrients back to the soil.
Examples of ground cover plants
- clover
- alpine strawberry
- creeping thyme
- chickweed
- wood sorrel
- low growing mints
Root Layer
The root, or rhizomatous, layer is an extension of all the other layers. Edible roots, rhizomes, and bulbs fill this layer, along with all of the roots of the other layers. Roots aerate the soil, creating channels for water and air that bring life to the soil.
Just like the aboveground layers, roots occupy different parts of the soil, from the surface to deep down in the soil profile.
Examples of root layer plants
- garlic bulbs
- onions
- potatoes
- yams
- sunchokes
- tigernut
Vine Layer
The vine, or vertical, layer adds a third dimension to the food forest. Vining plants use trees and shrubs or other structures as scaffolding to climb their way to sunnier places. It’s an excellent layer for increasing the productivity of the forest with food-producing vines, both perennial and annual.
Examples of vine layer plants
- fava beans
- green beans
- snow peas
- gourds and squashes
- cucumber
- grape
- kiwifruit
Two Additional Forest Garden Layers
The above list covers the original seven layers of a food forest, however, some people like to add two more layers to the bunch—the aquatic and fungal layers.
Aquatic Layer
Sometimes forest gardens intersect waterways or include water features such as ponds. This introduces a whole new layer of plants that grow along the water’s edge, floating, or submerged in water.
Aquatic plant examples
- cattails
- bullrushes
- watercress
- waterlilies
Fungal Layer
Fungi live within the soil and rotting wood, and on the roots of trees. Mushrooms can be another food grown in a food forest, but the value of this layer goes well beyond that. Mycelia networks are entwined throughout the soil in a complex system that, among other things, transport water and nutrients through the forest.
Examples of fungi in a food forest
Besides native fungi species that are found naturally in the soil and rotting wood of the forest floor, there are some edible species often introduced to a food forest, such as:
- shiitake
- oyster
- wine cap
Stacking Functions in a Forest Garden
Ideally, each plant in a food forest fills multiple functions. For example, an apple tree produces apples, but it also provides shade, its blossoms attract pollinators, and its dropped leaves provide mulch. Comfrey accumulates nutrients from deep in the soil with its long taproot, and its leaves make an excellent green mulch to protect the soil.
The multiple functions of plants
Producer
The stars of the food forest are the producers. These are the plants that produce yields for harvest, whether it be food, medicinals, crafting materials, or something else.
Mulcher
Many herbaceous and ground cover plants act as mulch, covering and protecting the soil. These green mulch plants, much like brown mulches, are important in a food forest. They help to hold moisture in and regulate the soil temperature, modulating the extreme temperature swings that occur on bare ground. When mulch plants get big they can be cut down and left in place to continue mulching. This practice is called “chop-and-drop.”
Accumulator
These deep tap-rooted plants take in nutrients from deep in the soil and store them in their leaves. Using the chop-and-drop method, the dropped leaf material mulches and breaks down, enriching the soil. Dandelion, comfrey, and mullen are examples of dynamic nutrient accumulators.
Fixer
Some plants, with the help of symbiotic organisms, can pull nitrogen out of the air, convert it to a usable form, and store it in nodules on their roots. When the roots die back, nitrogen is released to the soil where it becomes available to other plants. Because it takes root dieback to make this nitrogen available to other plants, regular pruning or cutting back of nitrogen-fixing plants is important. Some examples of nitrogen-fixing plants in a food forest are fava beans (or any legumes), black locust trees, and clover.
Attractor
These plants attract beneficial insects and birds to the food forest. Beneficial insects and birds include both pollinators, such as hummingbirds, and predators such as ladybugs. Most flowers, regardless of whether they’re on shrubs, trees, ground covers, or vines, attract beneficial insects or birds.
Aromatic confuser
These are also called repeller plants and include plants such as garlic and lemon balm. They have strong stents that can mask other plants and confuse pests that eat fruits or damage plants, keeping them away.
Trap
Trap plants don’t literally trap pests, but are more of a decoy, giving pests something to munch on instead of the plants we want to protect. A trap plant is more attractive to a pest than the crop we want a harvest from.
Suppressor
Suppressor plants fill in areas, both above and below ground, preventing weeds from coming in. Ground covers such as clover and mint, and densely planted bulbs are good suppressors.
Pioneer
These plants help a food forest get established. Pioneer plants are those plants that thrive in disturbed areas such as dandelions, sunflowers, and rhubarb. Since they are the first to revegetate disturbed areas, they shade and break up the soil, add organic matter, and make it easier for other plants to follow.
Nurse
Nurse plants provide shelter or scaffolding that helps young plants survive. Often, they are no longer needed and replaced after the new plants become established
Animals in a Forest Garden
Forest gardens aren’t limited to plants. Of course any ecosystem will include animals, and a forest garden is no different. Wild animals will visit or even take up residence, insects, spiders, earthworms, and all sorts of little critters will thrive, and the microbiome will flourish in a healthy forest garden.
But we can also choose to include animals deliberately in our forest gardens. A common choice is chickens, but other small animals such as rabbits make an integrated addition to a food forest.
To Sum Up
A forest garden (or food forest) is a food production system modeled after natural forests, but at a smaller scale and with an emphasis on food-producing species. Multiple layers of plants fill every niche of space in a forest garden, and every plant fills multiple functions to support other species and produce food.
For some ideas on how to start your own food forest, check out my other posts and references below.
References
Edible Forest Gardens by David Jacke with Eric Toensmeier
The Seven Layers of A Forest on Permaculturenews.org
Related Posts
A food forest is really just several guilds next to each other. Here’s my Ultimate Guide to Fruit Tree Guilds
Want some fruit tree guild examples? How about a simple apple tree guild example. Or, if you live in my part of the world, try a native edible guild for the Pacific Northwest.
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