Perennial Crops (original) (raw)

From Left to Right: Avocados | Breadfruit | Chestnuts | Pistachios.

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Call to action:

Expand the use of perennial crops to enhance carbon sequestration, restore and maintain soil health, and feed local communities.

Used by Indigenous and traditional communities for centuries, perennial plants produce food crops and diverse environmental benefits for years without replanting. In contrast, an annual plant completes its life cycle in one season. Most food crops are annuals. Staple perennial crops, such as nuts, olives, avocados, and beans, provide large amounts of carbohydrates, proteins, and other nutrients. Perennial vegetables, including bamboo shoots, asparagus, and leaves of the moringa tree, are rich in micronutrients. Other crops include fruits, berries, coffee, rice, and edible flowers. Perennial crops can be integrated into agroforestry and regenerative farming systems, boosting local food security. Once established, they are low maintenance and resilient to extreme weather. They can improve soil structure, protect land from erosion, improve water infiltration, and enhance carbon sequestration. Perennial crops are underutilized compared to annuals. Expanding their use will help long-term community and ecosystem health.

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Sources for each Nexus are graded numerically (-3 through 10), and the average is displayed as a letter grade. You can explore each source in depth by clicking “view sources” below. For more information, see our Nexus Ratings page.

Perennial Crops

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7.67

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Individuals

Learn what perennial crops are and why they are useful to human and ecosystem health. A perennial is any plant that lives longer than two years. An annual plant produces seeds before dying after one season. Twelve species of annuals provide three-fourths of all food, including corn, wheat, and rice. They are often grown as industrial mono-crops requiring extensive use of chemical fertilizers and pesticides, repeated every year. Perennial agriculture—including agroforestry and silvopasture—are nature-based food systems that have been in use around the world for centuries (see Agroforestry Nexus, Silvopasture Nexus and Agroecology Nexus). Perennial crops have many advantages:

• Perennials have been cultivated for thousands of years and remain a key component of Indigenous and traditional food systems today. Olive, date, carob, and chestnut endure as important crops. Acorns supported many human societies in a practice called balanoculture.
• There are over fifty perennial staple crops, including bananas, breadfruit, almonds, pistachios, walnuts, hazelnuts, coconuts, avocados, pecans, macadamias, and guáimaro nuts. Most grow in the subtropics and tropics. They are abundant in carbohydrates, proteins, fats, and micronutrients. Many are high-yielding and can provide the bulk of calories in diets.
• There are more than six hundred types of cultivated perennial vegetables, representing more than a third of all vegetable species. Here is a list.
• There are many types of perennial tree crops, including ones with edible leaves. The leaf of the moringa tree can be chewed fresh, cooked, or dried and added as a powder to staples such as bread flour.
• Perennial grain crops reduce the need for tillage, and their deep roots can increase soil carbon over time.
• Perennial crops can be integrated with annual crops into polycultures as a form of agroecology, particularly if livestock can be incorporated (see Animal Integration Nexus).
• Perennial crops support important ecosystem services, including soil carbon sequestration, pollination, improvement of water quality, and the slowing of soil erosion (see Farmers below).
• Many perennial crops are locally adapted and genetically cultivated for the conditions of a specific region, making them hardier to weather extremes. Perennial grain crops are being developed by cross-breeding annual grain species with wild perennial grass species. They provide more food for the world by increasing food production. Cultivating them can fight hunger, poverty, and malnutrition.
• Many perennial crops are classified as neglected and underutilized species (NUS), which have been overlooked or ignored by researchers, food companies, and policymakers for decades. See Wasting Nothing Nexus for more information.

Grow perennial crops at home. Producing food with perennial plants can be easy and inexpensive. They can be grown in containers or window boxes, incorporated into home and community gardens, or established in yards. There are many different combinations and designs for producing food from perennial crops at home. For an overview, this book details how a small backyard in western Massachusetts was converted to a highly productive perennial food garden and fruit-and-nut orchard in just a few years.

• There are many online resources for growing perennial crops at home. Nature Path, The Spruce, and WaPo provide overviews. Small Footprint Family and Plants Spark Joy have resources focused on perennial vegetables. Epic Gardening has a guide to growing perennial vegetables by hardiness zone.
• Eric Toensmeier, a perennial agriculture expert, has a 224-page guide to gardening perennial vegetables.
• Perennial crops can be part of a permaculture design. Tenth Acre Farm has a guide to creating an edible landscape, also called a foodscape. Both integrate food plants and trees with ornamentals.
• Here is a guide to growing perennial vegetables in a home greenhouse. Here is a guide to growing them in pots.
• If practical, consider growing a food forest at home. A food forest—also called a forest garden—is modeled after a natural forest. It includes fruit and nut trees, shrubs, and other perennial plants that work together to create a self-sustaining system. The goal of a food forest is to produce an abundance of food with minimal effort from the gardener. Orchard People and The Homesteading Hippy provide overviews. Here is a video on how to start a food forest. There are many DIY books on how to start and expand a food forest where you live. Here are ten examples of food forests around the world.
• Community food forests can involve one or more households working together to feed themselves.

Find support for growing perennial crops on social media. There are a number of online resources available via social media. Here are a few:

• Elementals and perennial vegetables group on Facebook.
• The Land Institute’s X and Facebook sites.
• Project Food Forest's Facebook Page.

Groups

Farmers and Other Landowners

Learn about the benefits of switching to perennial crops. The diversity of perennial crops, including vegetables, shrubs, and trees, as well as the variety of combinations by which they can be grown, offer farmers and landowners many choices on how to add perennial crops to their land and operations. Advantages of doing so include:

• Lower costs. Perennial crops can reduce the need for costly inputs associated with annual crops, including fertilizer and chemicals. It can lower the operational costs of tillage and planting, including fewer expenses for labor and machinery.
• More production. Perennials can produce a crop when annuals cannot and can grow in a broader range of conditions, such as desert, aquatic, and shade-dominated environments. Many perennial vegetables are woody species and are well suited to grow on marginal land or depleted soils.
• More diversity. Growing a variety of crops supports healthy, carbon-sequestering soils because it encourages diverse soil communities and distributes carbon at varying depths underground. Polycultures are better able to resist weather extremes and are more resilient in the face of droughts, floods, and other impacts of climate change.
• Erosion control. By remaining in place year-round, perennials reduce wind and water erosion. Farming with annual plants requires fields to be followed between growing seasons, leaving topsoil vulnerable to erosion. In contrast, perennial plants protect the soil surface all year and have deeper roots, which provide stability to soils.
• Reduces chemical runoff. Annual crops have been shown to lose up to thirty-five times more nitrogen than their perennial counterparts. Chemical fertilizers and pesticides that are not completely absorbed by annual crops often migrate into waterways and accumulate downstream.
• Increases water-use efficiency. The roots of perennial crops can grow eight to ten feet deep and are more fibrous than annual plants, whose roots often reach only twelve inches, enabling perennial crops to reach and retain soil moisture more efficiently. This means less water use for the farm and more resilience in a drought.
• More efficient nutrient cycling. Perennials more efficiently take up nutrients as a result of their extensive root systems, reducing the amount of nutrient supplementation required to keep plants healthy.
• Increased light interception efficiency. The diversity of perennial plant types, their earlier canopy development, and longer green leaf duration, all combine to increase their light interception efficiency, an important factor in plant productivity.
• Less fossil fuel use. Annual systems require fields to be tilled and replanted much more often than perennial systems, requiring higher levels of fossil fuel use.
• Intercropping. Perennials, such as switchgrass and alfalfa, can be intercropped with annual crops in no-till systems.
• Greater carbon sequestration and more soil organic matter. The longer growing seasons of perennials, the decomposition of their leaves on the soil surface, and the varied depths of their roots combined with their ability to grow in a wide range of landscapes mean they can add more carbon to the soil over a longer period of time than annual plants.
• Greater resilience. All these attributes combine to enhance ecosystem and agricultural resilience, buffering food systems against the deleterious effects of climate change.

Implement perennial food production on your farm. Perennial agriculture can take many forms on your farm depending on region, operation, goals, and finances. Perennial crops can be integrated with annual crops, or they can replace them altogether. On larger farms, food forests or other types of agroforestry can be created using perennials. One obstacle to implementation can be productivity—at least by a conventional definition. Many perennials, particularly fruit and nut trees, take years to yield a profitable crop after planting. Compared to annuals, perennials generally have lower yields per acre. Weeds and pests can lower yields as well. Options and elements for implementation include:

• Fruiting hedgerows at the edges of farm fields can provide a perennial crop while creating habitat for wildlife and beneficial insects.
• Alley cropping is a type of agroforestry that utilizes trees and shrubs, which are planted in rows often separated by a horticultural crop. The trees and shrubs can produce crops of their own (see Agroforestry Nexus).
• Perennial cover crops, or perennial pastures, can create diverse forage for livestock. Flowering plants, as part of the mix, can attract bees and other beneficial insects.
• Perennial tree crops can add diversity to your operation. The Savanna Institute has a guide to planting tree crops.
• A food forest is land covered with edible perennial plants designed to mimic the edge of a forest. It can be as small as one-tenth an acre or hundreds of acres. Mark Shepard’s New Forest Farm in Wisconsin is a prime example. The goal is to create layers of plants on the land, with tall trees sheltering smaller ones interspersed with perennial shrubs, bushes, herbs, flowering plants, mushrooms, and even vines. Food forests are diverse, high-yielding, multiseasonal, and relatively low maintenance.

Consider perennial grain and rice production. Globally, nearly all grain grown as a crop is produced by annual plants. Seeking an alternative, researchers have for decades been trying to perennialize grain by crossbreeding an annual grain species with a wild perennial cousin. The goal is to create a commercially viable grain that maintains a quality similar to the annual parent while inheriting the perennial traits from the other parent. A similar and more recent effort has focused on perennial rice, currently under development. Both types of perennialized grains have important advantages and disadvantages:

• Perennialized grains exhibit many of the benefits of the other perennial crops, including reduced tillage, reduced inputs, enriched soils, increased carbon storage, and more efficient nutrient and water cycling. An example is Kernza, a hybrid perennial grass developed by researchers at the Land Institute in Kansas under the direction of its founder, Wes Jackson. After years of experimentation, Kernza hit the commercial market and can be found in cereal, pasta, pancake mix, and beer. It is often pitched as a climate-friendly alternative to conventionally grown cereal grain.
• The market penetration of Kernza, however, has been small so far. The number of acres under cultivation is small as well. Kernza’s yield per acre is one-quarter of conventional wheat, though researchers are making steady progress in bringing yields up. Kernza is expensive for buyers, costing up to twenty times more than conventionally produced wheat.
• Perennial rice—called PR 23 and developed in China—has the potential to benefit the soil, as well as reduce deforestation by keeping land out of the fallow stage for longer periods of time. Its perennialism could save smallholder farmers considerable labor and expense. However, researchers discovered that yields of PR23 drop quickly after a few years, requiring replanting.

Researchers

Expand research into perennial crops. There is a need to establish several agricultural research stations to study varieties of trees, grasses, and other perennial plants adapted to the local climate, soil, and people’s cultural practices. Studying local soil types and finding ways of improving them are also critical.

• The International Initiative is a program of the Land Institute that is encouraging researchers and others to accelerate the transition from annual monocultures to perennial polycultures in agriculture.
• Research into perennial rice and oil crops is beginning to broaden as well.
• Plant breeding programs need more personnel, on-the-ground trials, and technological innovation.
• There is a need for international coordination, scientific exchanges, conferences, identification of priority croplands, and training programs for young scientists in ecology, perennial plant breeding, and crop management.

Companies

Create market demand for products made from perennial crops. The dominance of annual crop systems limits the supply chain infrastructure and regional markets for perennial crops. In particular, food distribution companies could support start-up businesses that are trying to get perennial foods to market.

• The Perennial Pantry is a community-supported agriculture (CSA) organization that sells products made from Kernza grain.
• The Perennial Foods Group sources regeneratively grown food across Africa.

Shift federal and state policies to support perennial crop production. In the United States, the Department of Agriculture (USDA) supports annual crop systems over perennials. This is in contrast with China, where the government supports the development of perennial rice. In Australia, the government of New South Wales supports perennial wheat breeding programs. Changes in policy can begin to shift education, conservation, insurance, and research programs to support perennial agriculture. For example:

• Allow tree plantings to be eligible for crop insurance until maturation.
• Create policies that cover the lifetime production of a perennial crop.
• Allow perennial crops to be eligible for direct payment programs (as most annual crops are).
• Direct conservation programs to include perennial agriculture.
• Make long-term research grants available for the development of perennial crops.

Key Players

Project Food Forest (South Dakota, U.S.) empowers people to feed themselves through agroforestry, edible landscaping, and education.

Crop Trust (Germany) works internationally to protect agricultural diversity in cooperation with farmers, researchers, governments, and NGOs.

The Savannah Institute (U.S.) envisions a multifunctional agriculture in the Midwest US based on agroforestry systems of integrated trees, crops, and livestock

World Vegetable Center (Taiwan) works to create a more resilient world through greater diversity in what we grow and eat.

Green America (U.S.) works along the supply chain from farmers to consumers to ensure a safe, just, and sustainable food system.

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