Soil cultivation is any process that re-arranges the soil by using some activity. For farmers, cultivation typically means running a tractor over their field with a plow or disc to break up the soil’s surface. This is done prior to planting.
In the landscape, garden or lawn, we do the same thing. For small gardens this is usually done by hand with a shovel or fork. For larger areas a roto-tiller may be used. For lawns, an aerator is the best tool.
Care has to be taken not to over-cultivate the soil. Several bad things happen when we over-cultivate. Cultivation disrupts the soils natural structure. Extreme cultivation as is done with a roto-tiller, pulverizes the soil’s structure in such a way that it may become even more compacted in a short period of time. Cultivation also brings weed seeds to the surface that may become a problem. Extreme cultivation also destroys earthworm populations.