A cultivator loosens ground and/or removes weeds from a garden or farm where crops are growing. A cultivator can be a person, a garden-implement hand tool or a machine. Cultivation keeps plants from having to compete with weeds for water and nutrients. Cultivation also relieves compaction in the soil, allowing oxygen to more amply reach plants' roots and allowing rain to penetrate the soil surface before running off.
Humans as Cultivators
While the word "cultivator" has come to be used more as a term for farming and gardening implements, a cultivator is first and foremost the person who tends the plants. And cultivating is more than just weeding and turning soil; cultivating is all of the work necessary to keep crops healthy, such as irrigating, feeding and mulching.
Simple Cultivation Tools
Hoes, garden forks, pickaxes and plows were all designed to loosen the soil before planting; history suggests such tools were used as early as Mesopotamian times. These tools are still used today to remove stubborn weeds from the ground after planting. When the practice of planting in rows became prominent, the hoe became the most important of these tools, as a hoe can remove weeds, maintain rows and aerate soil.
Horse or mule-drawn cultivators designed to straddle more than one row first appeared in 1865. From then, a steady stream of new ways to pull a cultivator followed: first steam-powered tractors, then lightweight gasoline-powered tractors, then heavy-weight multiple-gear tractors. As the power of the pulling device grew, so did the size of the cultivators dragged behind them.
The advances in cultivation tools have helped to reduce the amount of labor hours required to plant, tend and harvest a crop ten-fold since the 1830s. The reduction in labor required means that more, larger crops can be produced by a single farmer. By 1990, one farmer could supply the one-year food requirements for 100 people.
Machinery requires less labor but more energy. This energy comes from fossil fuels such as coal or oil, resources that are limited. Machinery requires even crop rows of a single type of plant. Monoculture, or vast fields of the same crop, has proven to increase pest populations, requiring massive amounts of chemical to keep an infestation in check. Constant soil cultivation also decreases the soil's ability to retain moisture and accelerates loss of nitrogen to the atmosphere.