Definition: A technique where vegetative barriers are planted along the contours or “level” lines of hillsides and slopes to stabilize soils and increase soil moisture and fertility.
Contour Planting in the Forest Garden:
Contour planting is helpful for mitigating soil erosion and runoff on hilly or sloped land. On flat land, properly managing the landscape and incorporating agroforestry techniques - such as alley cropping, and windbreaks - can lead to a more stable and fertile soils. Soil erosion has an increasingly detrimental impact on the stability and fertility of the soil as the slope increases. During rains, runoff will flow down the hillside and carry away topsoil along with all its nutrients. To help mitigate this runoff, contour planting is recommended on slopes with an incline greater than 5%.
When developing contours with trees or other plants, the trees are planted closely together along pre-determined contour lines, using the assistance of a tool called an A-frame. As the plants grow, their roots bind the soil below while the branches help trap soil from runoff above, eventually forming a small ridge or dam. When water reaches this ridge, it slows or stops flowing, forming a puddle, and has more chance to percolate into the soil. Over time, the land levels out behind the contour, creating terraces.