The main mass of roots at the base of a plant located directly beneath the stem. The term is most commonly used when referring to transplanting a plant and the need to protect the roots.
Root Balls in the Forest Garden
When transplanting a seedling, it is important that the root ball be handled carefully so that the plant can have the best start possible. When roots are damaged, it stresses the plant. Some roots are cut or lost during the transplanting process as you separate the seedling from the nursery environment, whether bare root or tree sack, but the more roots that can be kept intact, the easier it will be for the plant to transition to its new growth location. Additionally, unless you are using bare root seedlings, it is good to keep the soil around and in the root ball, rather than removing it. Farmers dig holes at least twice the diameter of the seedlings root ball, and then fill the hole with amended soil. This allows the roots enough space to spread out and establish in good soil. Allowing for adequate space also enables farmers to make sure that the roots are not too compacted in the soil and won't be restricted or tangled in their growth.