Commercial fertilizers, materials containing plant food which are bought and sold in the markets to improve the soil.
Compost, a mixture of decaying organic matter used to enrich the soil.
Cross pollination, the pollination of a flower by pollen brought from some other flower.
Cover crop, a crop to cover the soil during the interval between regular corps.
Cultivator, a farm implement used to loosen the surface of the soil and to kill weeds after a crop has been planted.
Cutting, a part of a plant placed in moist soil, water or other medium with the object of its producing roots and making a new plant.
Dormant, said of plants when they are resting or inactive. Most plants are dormant during the winter season.
Drainage, the method by which surplus water is removed from the land.
Element, a substance that cannot be divided into simpler substances.
Fermentation, the process by which organic substances are broken down or changed and new substances formed.