A disc cultivator is a garden cultivator which consists of a series of rotating discs mounted on an axle. The discs cut through the soil to loosen up clods and aerate it in preparation for planting. Typically, a disc cultivator is designed as an attachment for a tractor, with the tractor towing the cultivator through the field, and this particular style of cultivator is designed for cultivating large fields. For smaller areas such as home yards and gardens, a small rotary tiller may be more appropriate.
Cultivators serve a number of functions. They are designed to break up the soil so that if it has become compacted, it will be loosened, and to normalize the texture of the soil. The cultivator removes large clods and turns up rocks which might impede plant growth. The height can usually be adjusted to determine how deeply the soil is worked, with people adjusting the height for different crops and different needs.
A disc cultivator can also be used to work in soil amendments such as straw, compost, fertilizer, peat, and so forth. The action of the cultivator pushes the soil amendments into the soil, blends them well, and leaves the mixture thoroughly aerated. Some people also run cultivators over existing crops which had died back to work them back into the ground as a source of nutrients. For example, after a wheat crop has been harvested, a cultivator could work the remainder of the stalks back into the soil, where they will provide enrichment.
People typically run a disc cultivator to prepare the soil for planting. Once the soil has been loosened, amended if necessary, and aerated, the crop can be sown by hand or with a tractor. In the loose, rich soil, the seeds should quickly germinate and take hold, extending their root networks deeply into the soil to reach water and nutrients. Farmers can adjust the level of nutrition and the pH in the soil to meet the needs of specific crops.
Disc cultivators cannot be run when the soil is wet. The weight of the tractor will compact the soil, and the cultivator will tend to compact the soil as it is moved through the ground. This is not desirable. While it is safe to run such devices in moist or rainy weather, as long as the soil isn't soaking wet, in areas where winters tend to be soggy, people need to take care to use a disc cultivator on a day when the soil has had a chance to try out.