How to Plant a Sustainable Food Forest That Yields Layers of Produce

While you may have a few edible plants growing in your backyard, have you ever wondered what it would be like to eat fruits and vegetables produced exclusively by your landscape? One way to make this a reality is by planting a food forest, a very old, traditional type of agroforestry that's popular in the tropics. In recent years, food forests have become increasingly well-known in urban areas as a climate-smart approach to agriculture. While food forests exist in some major cities as a way to feed local communities, they're something you can create in your own backyard with proper planning.

What Is a Food Forest? 

As its name implies, a food forest is a system in which edible, harvestable crops are produced in a multi-story setting. "The plant material is purposefully selected and organized in such a way that it appears similar in form to a natural, layered forest, rather than a monoculture row of crops," says Damon Abdi of the Hammond Research Station at Louisiana State University's agricultural center. The tree-based system incorporates multiple layers of edible root crops, vines, herbaceous plants, shrubs, and trees to meet the needs of the grower. They can be grown in your own backyard to feed your family, or in a public setting designed to benefit entire neighborhoods, schools, and other communities. 

Benefits of Growing a Food Forest 

There are many benefits of growing a food forest. "Socially, the benefits of a food forest include providing fresh access to edible crops, particularly in food deserts and areas lacking equitable access to produce," says Abdi. On an individual level, this style of gardening is a more sustainable way to source produce, as fewer external inputs, like chemical fertilizers and pesticides, are needed. 

Layers of a Food Forest 

The number of layers you need to successfully build a food forest vary from grower to grower, but seven tiers is standard.

Canopy 

The canopy layer is where the largest trees (such as a walnut tree) in your food forest should go. "These will provide the greatest amount of shade, protecting more sunlight-sensitive species below," says Cara Rockwell, assistant professor with Florida International University's institute of environment and department of earth and environment. "These trees are a great source of carbon storage in the food forest—an important aspect of climate-smart agriculture." Additionally, leaves from the canopy layer fall and compost in the soil below, becoming nutrients for the rest of the garden. 

Mid-Canopy 

Following the canopy layer is the mid-canopy, which is composed of shorter trees. "Perhaps more practical as the top layer in small backyard food forests, trees at this layer are commonly fruit trees," says Abdi. "Apples, cherries, and pears are examples of fruit crops that would work in this regard."

Shrub

Smaller, woody shrub species make up the lower canopy layer. Keep in mind that when you first plant your shrubs, they might be taller than the tree saplings next to them, but over time, the larger trees will grow to shade them. When selecting your shrubs, look for shade tolerance labels to account for this. Good candidates for the shrub layer include blueberries, currants, elderberries, and raspberries.

Herbaceous Plants 

Non-woody plants—usually perennials—compose this tier. "Plants such as asparagus, garlic, or horseradish are good for this," says Abdi. "Many culinary herbs, including basil, cilantro, and thyme are suitable for this purpose."

Ground Cover 

The ground cover layer is extremely important, as these plants prevent erosion and provide cover for the soil. "Ground cover crops add extra value by acting as a living mulch to suppress weeds from growing on the food forest floor," says Abdi. "Consider using varieties of mint, creeping rosemary, or perhaps strawberries."

Vines

Wrapped around trunks or large stems, vines add beauty to your food forest. “Crops that typically grow on trellises and on other supporting plants can provide added intrigue to a food forest," says Abdi. "Grapes, beans, cucumbers, and other crops are good candidates for this purpose."  

Root Crops 

Don't forget about what goes on underneath the soil, too. "Root crops are great for the substrate, as they help stabilize the soil," says Rockwell. These crops can include anything from potatoes and ginger to taro and carrots.

Fungi

If you want to add an additional layer, some growers include a section for fungi. "While soil will naturally include mycelium and other fungi, these can be amended by planting mushrooms," says Kim Jordan, co-executive director of the Philadelphia Orchard Project.

Choose a Location for Your Food Forest

Growing a food forest requires careful planning and meticulous attention to detail. You may want to scout a few different locations for a year before deciding on where you put your food forest. This will give you time to understand what type of sunlight the area receives, what its natural irrigation is like, the type of pests it encounters, and other important factors. 

Sunlight

Some food forest species prefer more sun exposure than others. "For the shade-loving components below, the upper canopy will dictate how much light is filtered through," says Abdi. It's easier to choose a location that meets the sun exposure requirements of the upper canopy and then use the canopy to reduce the amount of light transmission, rather than not having enough sunlight to begin with.  

Soil

Test your soil before getting started, which will help you gain an understanding of your soil's pH and what amendments it may need. In general, soil with good drainage that maintains its moistness is optimal for a food forest. "If the soil quality is poor, the soil can be built up through composting and mulching," says Rockwell. "The idea is that once the soil substrate has been established, it should be disturbed infrequently, so as not to disturb perennial plant roots and the biotic below ground community, like bacteria, fungi, insects, and more."

Water

Your food forest's watering needs will vary depending on your location and the types of plants you're growing. "A mature, deep rooted tree may not need the supplementary water that is essential for more juvenile crops, or those that are not deep-rooted and well established," says Abdi. "While depending on routine irrigation is seldom a primary concern with a food forest, having access to water will be invaluable in areas that are particularly prone to extended droughts or where a supplementary splash is desired."

Plan Your Layout

How you design your food forest will depend on your location, how much space you have, other existing plants, inclusion of benches, tables, and other gathering areas, and more. "There is no right or wrong order for a food forest to be planted, but we generally start by sketching out a map or design that shows how large the mature trees are expected to be," says Jordan. "In larger spaces, there might be separate areas for berry gardens, rain gardens, or pollinator gardens, but for the most part the trees, bushes, vines, and pollinators will be commingled in each space."

Consider the Growing Habits of Your Plants

One of the most important things to consider when mapping your layout is the growing habits of the varieties being planted. "This means keeping in mind the full size a tree will reach at maturity (height wise and canopy wise). Think about what it could do to prevent sunlight from accessing the ground," says Jordan. "Because of this, sometimes the ground layer may need to be replanted after several years if the mature tree provides too much shade to allow fruit to fully ripen."

Focus on Companion Planting

Guide your layout by thinking about what plants grow well together and which mutually benefit each other. For example, sunflowers help provide support for climbing vines and shade for crops that can't stand up to full-sun conditions.

Prepare the Soil

Once you know where you want your food forest to go and a general layout, you can begin preparing the soil for planting. "To help keep down weeds in the future, we generally will do some sheet mulching 6 to 12 months ahead of the initial planting," says Jordan.

1. Mow the area as short as you can.
2. Lay down one layer of ink-free cardboard, overlapping the pieces so no grass is showing.
3. Water cardboard to start the breakdown.
4. Top the cardboard with about 6 inches of compost.
5. Top compost with a carbon-rich layer, like wood chips or mulch.
6. Create a hole in the mulch and plant into the compost below.
7. Continue regular watering.

Add Your Plants

Once the soil is ready, you can add your plants. "Generally, we plant trees and larger shrubs in the fall to allow their root systems to establish over the fall and winter, so they are stronger and better able to handle harsh summer temperatures," says Jordan. "With smaller plants including herbs, pollinators, and ground covers, we plant in spring or fall."

Be sure to incorporate some non-edible crops that encourage biodiversity. "This can increase pollinator populations which in turn can lead to more bountiful harvests," says Abdi.