Mmmmmm….Soil Health
Here at Veggielution, we strive to be more than just another farm. As an urban farm situated in a valley once known as an agricultural powerhouse, we have the power to reshape the narrative of what farming means for the valley today. In spirit, this means using the farm as a base of community knowledge and empowerment. In practice, this means approaching the farm landscape with the most dynamic and innovative techniques that agriculture has to offer. Examples of such techniques currently in place are our native hedgerow, meant to provide habitat for beneficial birds and insects, or our use of compost fertilizer, intended to maximize productivity while minimizing off-farm pollutants. This year, we are introducing a new and exciting strategy to promote soil health: No-till Farming!
What’s different about No-Till? — No-till is a planting system where the soil is left undisturbed from the harvest of one crop to the planting of the next. At the end of a season, plants typically are cut at the base and residue is left on the surface of the field, while the roots are left in the soil to decompose. This is very different from conventional farming, where old plants are entirely removed after a season, and tractors till the field, aerating the soil and shaping beds for future planting. While there are certainly benefits to tillage, the potential consequences of such intense soil disturbance can be immense. Tillage has long-term negative effects on soil structure and fertility, as well as the potential to create an impermeable layer called “plow-pan,” which can prevent water from making its way through the soil profile. No-till management is meant to counteract all of that.
Soil Organic Matter and Fertility: Without the stress of disturbance, the soil ecosystem flourishes. The decomposing root systems and fresh plant residue that were left in the field attract microbes, funguses, earthworms, and other helpful decomposers — all of which comprises a network called “soil organic matter.” These decomposing communities interact with the soil, the plant residue, and each other to convert inaccessible nutrients into new forms that are readily available to plants.
Soil Structure and Water infiltration: No-till allows the soil organic matter to form soil aggregates, creating a more porous and stable soil. Air and water are overlooked components of a healthy field, and a robust structure makes it easier for both to travel freely under our feet. This is especially crucial in San Jose’s clay soils, where water quickly saturates the top layer of soil, but may not reach deeper into the soil profile. These pathways also facilitate extensive root growth, allowing plants to reach deeper nutrient stores.
Climate-Change Resilience: This practice directly contributes to our strength in the face of global warming. The plant residue left on the surface acts as a mulch, helping to stabilize soil temperatures no matter how variable the climate gets. Additionally, the mulch significantly reduces the potential for wind and water erosion, protecting us from soil-loss in the case of severe weather events. Finally, though somewhat controversially, no-till fields can act as a form of carbon storage. Carbon is sequestered from the atmosphere into the upper layers of soil, where it can be used up by plants, or simply remain dormant for as long as the field remains undisturbed.
Although no-till is a new frontier for us, we are extremely excited to get it underway. Much of our farm will remain under reduced tillage, cultivated through the summer and fall under an 8 year crop rotation. We let these fields regenerate their nutrients in winter and spring through the use of mixed cover-crops. Our no-till plots will be under year-round cultivation, although they will use a limited crop rotation that excludes summertime, heavy feeder plant families. Compost will be applied as needed throughout the year. As with our other fields, we plan on utilizing soil tests to monitor our soils, and make sure that our practices are aligned with our goals.
PS: I don’t know where or how, but somewhere in the soil health post ya gotttttta say something about how we “don’t treat our soil like dirt”
Written by Jason Rodriguez, Veggielution Farm Apprentice
