What is a food forest?

A food forest is a way to grow food by working with nature; a designed food-growing ecosystem that mirrors the structure and function of a natural young woodland or woodland edge.

At the heart of a food forest is the integration of some core principles:

• No-dig gardening – letting soil ecosystems thrive undisturbed.
• Perennial planting – reducing the need for constant replanting.
• Mulching – feeding the soil and protecting it from erosion.
• Polyculture – growing diverse species together for balance and resilience.
• Stacking functions – designing elements to serve multiple purposes.

These principles come together to create what is known as a food forest/forest garden/woodland garden - a layered, low maintenance, food producing ecosystem.

 

   

These two images highlight the core principles of polyculture, stacking, perennial planting & no dig. The young fruit trees are underplanted with currant bushes and species such as comfrey, burdock, sweet cicely, knapweed & hogweed amongst others. Some of these are edible and others are native 'weeds'. Every species plays a role in the system. Whether its edible crops, attracting pollinators and other beneficial insects or deep roots to mine the deeper levels of soil for nutrients. Nitrogen-fixing sea buckthorn shrubs contribute fertility to the system as well as an edible crop. 

 

Food forest or woodland?

The word ‘forest’ conjures up different images for different people. Much of the tree coverage in Ireland is in the form of densely planted timber crops of non-native, fast growing conifers such as Sitka spruce and Fir. Sadly, very little of Ireland’s natural woodland remains. In our temperate climate, woodland is the natural climax ecosystem; if you left a patch of land alone long enough, it would naturally develop into woodland through ecological succession.  A food forest mimics the structure of a young woodland. However, instead of ecological succession, the creation of a food forest is guided by the designer and the ecological limitations of the site. Most importantly, this in done in a way that meets human needs without disrupting nature’s patterns. One key strategy is using the edge effect; edges between ecosystems (like where a field meets a woodland) are hotspots of biodiversity. The more edge you create in your food forest, the greater diversity and potential productivity it will support. This is the reason why a food forest may often have multiple glades, openings, wider spacing of trees or even some patches of open meadow. Annual vegetable patches may also be incorporated into some of these spaces where there is maximal sunlight.

 

A developing native woodland at the southern edge of our farm. Note the variation in structure and diversity of species.

 

The seven layers of a food forest

A mature food forest is designed in layers:

1. Canopy – tall fruit and nut trees.
2. Shrub layer – berries and smaller fruit trees.
3. Herbaceous perennials – vegetables and/or herbs that return yearly. This layer can also include native ‘weeds’ that provide roles in attracting pollinators or other beneficial insects.
4. Ground cover – plants that suppress weeds and retain moisture.
5. Climbers – vines like grapes or kiwis that use vertical space. This layer is usually planted after a number of years when the canopy layer has developed.
6. Underground layer – root crops like garlic, onions, and Jerusalem artichokes
7. Fungal layer – mushrooms and beneficial fungi. This may also include growing trees as coppice to harvest logs to grow mushrooms.

Depending upon the size of a food forest, some layers may not be included, for example, in a small space, the shrub layer may be the tallest layer. Additionally, some plants may fulfill roles of multiple layers, eg; some herbaceous perennials provide excellent ground cover so a ground cover layer beneath them may not be necessary. 

 

A young apple tree that will form the canopy layer, a whitecurrant bush as the shrub layer, knapweed, comfrey & dandelions as the herbaceous perennial/ground cover layers. Climbers such as hardy kiwi will be incorporated in a number of years.

 

Benefits of a food forest

The advantages of this system are as layered as a natural woodland:

• Low maintenance, high efficiency – after initial design and hard work in terms of establishment and the incorporation of nitrogen fixing trees to supply a sustainable source of nitrogen, a food forest is relatively low maintenance.
• Diverse yields – fruits, nuts, vegetables, mushrooms, herbs, fuel, fibers and medicine.
• Resilience to climate extremes – deep-rooted perennials and multi-species planting offer built-in stability to the ever-increasing instability of our climate.
• Ecological value – food forests sequester carbon, store water, and provide habitats for wildlife.

 

Insect diversity on our farm has increased year on year. Biodiversity conservation & climate-resilient, sustainable food production are our key objectives.

Challenges & limitations of food forests in Ireland

While food forests are incredibly promising, they do come with challenges especially in Ireland’s cool, damp conditions.

• Limited sunlight. Reduced levels of photosynthesis and poor fruit development/ripening can limit the productivity of plants.
• Waterlogging can result in root rot and disease.
• Wind can cause damage and limit pollination in certain circumstances.
• Fungal diseases and pests are more prevalent in humid environments.
• Not all species thrive in Ireland’s climate.

Design considerations including but not limited to; windbreak establishment, wider tree spacing, more traditional tree layouts within the wider food forest, choosing site-appropriate species and the use of native plants to attract beneficial insects are all examples of how some of these challenges can be overcome. No two food forests are the same. Each is designed with a set of goals, constrained and guided by the current and future climate and site limitations. 

Conclusion

The term 'food forest' may imply that huge swathes of land are required. Whether you are working at field scale, in a backyard, or even an urban plot, a food forest is a way to build sustainable abundance, resilience, and biodiversity, while letting nature lead the way. Fundamentally, the key to the successful design of a food forest lies in the diversity of species, their mutualistic relationships and a keen focus upon protecting, building and maintaining healthy soil.