In veganic agriculture, fertility is maintained without the use of chemical fertilizers or animal products. Instead, veganic agriculture favors good soil stewardship, biodiversity, plant-based fertility (compost, mulch, chipped branch wood, green manures), and mineral supplements if needed. Veganic aims for a closed system, striving to maintain fertility using the materials available on the farmland. When inputs are needed, regionally-appropriate local materials are strongly preferred. Biodiversity is encouraged on the holding to create a vibrant community of plants and free-living animals, leading to improved soil fertility, disease-resistance, and balanced insect populations.
Note: Veganic agriculture is compatible with other approaches to agriculture, such as permaculture, field-scale agriculture, biointensive, and no-till (learn more here). We also highly recommend reading the introductions to veganic techniques written by The Vegan Organic Network and Plants for a Future.
Soil Stewardship and Biodiversity
Retaining existing soil nutrients: The most vital way of maintaining soil fertility is to ensure that existing nutrients are retained. Uncovered soil can lead to topsoil loss and nutrient leakage when exposed to wind and rain. Keeping the soil constantly covered with crops, mulch or green manure will help ensure that existing nutrients in the soil are not needlessly washed away.
Nourishing and protecting the soil food web: Healthy soil is thriving with a diverse community of earthworms, fungi, and thousands of species of microorganisms. By feeding the soil life with organic plant matter, such as compost, mulch, and green manures, the soil organisms are able to break down this material into a form that is accessible to growing plants. These organisms act as the natural digestive system of the soil, eliminating the need to add manure. The soil organisms, especially earthworms, improve the structure of the soil by creating pathways and a crumbly soil structure. Fungi, such as mycorrhizal fungi, can increase the availability of phosphorus, potassium, and other minerals. Tillage and digging can damage the soil life and soil structure, so no-till or low-till techniques are highly recommended.
Polyculture and crop rotation: Each type of plant places different demands on the soil: for example, some plants require higher amounts of nitrogen or calcium. Different plants also provide the soil with certain advantages, like fixing nitrogen or mining deeply for nutrients. If we plant monocultures, or leave annual plants in the same place year after year, the soil can become depleted of particular nutrients. By planting a wide variety of crops and rotating their position each year, a healthier nutrient balance can be maintained. By including green manures in the crop rotation, nutrients and organic matter can be added back into the soil. Crop rotations also aid in diminishing losses by discouraging diseases and competing insects from becoming established.
Biodiversity of free-living animals: Veganic growers encourage the presence of free-living animals on their land by conserving or installing appropriate habitats—trees, hedgerows, ponds, flowers. The vast majority of free-living animals have a beneficial or neutral effect, and they contribute vital functions like pollination. By encouraging a diverse ecosystem of free-living animals and insects on the holding, it is less likely that a single species will overpopulate the area and cause crop damage.
Perennial agriculture: While veganic agriculture with annual plants such as tomatoes and cucumbers is a fine way to garden, there are compelling reasons to consider perennial plants. Perennials will produce for years with minimal tending, and their deep root systems can draw up minerals and water, with the potential to become self-fertilizing and self-watering.
Local plant-based fertility
Compost: Composting is the most essential act for completing the nutrient cycle in our farms and gardens. “Green” materials like food scraps are mixed with “brown” materials like dry leaves, twigs, and straw. These are decomposed by microorganisms, making nutrients available for plants. For home gardeners, compost can be the main source of veganic fertility.
Mulch: Mulches are materials that cover the soil. Organic mulches such as hay will decompose and feed the soil microorganisms, which in turn feed the plants. Mulches protect the soil from wind and erosion, help retain moisture, moderate the temperature of the soil, and impede the growth of competing plants.
Chipped Branch Wood: Chipped Branch Wood is a fertility technique using the small branches of deciduous trees. While tree trunks contain a carbon/nitrogen ratio that is imbalanced for agricultural purposes, small branches under 7 centimeters in diameter are high in nutrients and have a favorable carbon/nitrogen ratio. In the Chipped Branch Wood technique, these small branches are chipped and used as a mulch, or incorporated with top layers of the soil in combination with a nitrogen-fixing green manure. The branch chips are broken down by fungi and soil microorganisms, creating a stable humus similar to that of natural forests.
Green manures / cover cropping: Green manures are plants which are grown to be cut down before going to seed, and incorporated with the soil (or, alternately, they could be used as a mulch). Green manures can be grown for many purposes, and are often multifunctional. Any plant can be grown as a green manure, though usually plants are chosen which are nitrogen-fixing, or which will add significant biomass to the soil. Green manures can be grown for an entire season, to help build up the nutrient content of the soil, or grown underneath a crop (undersowing), or grown after the main crop of the season (cover cropping) to ensure that the soil is not left exposed.
Additional local plant-based fertility
- Leaf mould: Leaves that decompose for a year can then be used in potting soil and seedling mixtures or as an amendment. Place leaves in a garbage bag, poke holes in the bag, and use after one or two years.
- Local biomass: Look for local sources of biomass in your region, such as seaweed, spent hops from breweries, waste from the food industry, etc.
- Plant meal: Alfalfa meal, peanut meal, soybean meal, etc, can often be sourced locally to add a boost of nutrients including nitrogen.
- Liquid feeds: Favour local liquid feeds, such as homemade comfrey tea, nettle tea or compost tea.
- Soil inoculants: Inoculating the soil with microrrhizal fungi can increase nutrient uptake (especially phosphorus and potassium) and will survive year after year with good soil stewardship.
- Though not plant-based, veganic gardeners may also wish to use their humanure or urine to ensure that the nutrients they consume are given back to the soil.
Plant and mineral inputs
To the greatest degree possible, veganic agriculture aims to minimize the use of off-farm products, especially those which are imported long distances. When we bring materials such as compost and bagged fertilizers from other places, there is a fossil fuel cost associated with their transport, and more importantly, we are removing a source of fertility from another region. Peat especially, though it is plant-based, has significant environmental consequences. In the case of mined mineral supplements, there is an environmental toll to consider related to their extraction and processing.
Nevertheless, inputs can be very useful for new farmers and gardeners who are not yet generating their own fertility, for those who live in apartments and have no access to local soil or fertilizers, for greenhouse growing and propagation of young seedlings, and for addressing nutrient deficiencies in the soil. Products like seaweed meal and organic alfalfa meal provide a nutrient boost from renewable plant sources. There may even be inputs available in your bioregion that would otherwise be added to the waste stream (such as waste organic matter from restaurants, tofu factories, breweries, and the nut industry), making certain inputs a proactive environmental initiative.
Imported mineral supplements are sometimes used in veganic growing to address specific nutrient deficiencies following a soil analysis. If a grower begins to farm or garden in an area where the soil has already been depleted by unsustainable agricultural practices, mineral supplements could be used to return the nutrient levels to a normal range. Some farms may also need periodic boosts of micronutrients like boron to ensure a healthy crop. Mineral supplements in veganic agriculture can include lime, rock phosphate, dolomite, rock potash, gypsum, and green sand.