Hmmmm...... Organic matter, excreted by animals, which is used as a soil amendment and fertilizer. Green manures are plant cover crops which are tilled into the soil.

Mineral elements which are needed by some plants in very small quantities. If the plants you are growing require specific 'trace elements' and they are not available in the soil, they must be added.

Variations of the climate within a given area, usually influenced by hills, hollows, structures or proximity to bodies of water.?(i.e. when it's raining at your house, and the sun is shining on the other side of the street)

Plants bearing separate male and female flowers on the same plant

Any loose material placed over the soil to control weeds and conserve soil moisture. Usually this is a coarse organic matter, such as leaves, clippings or bark, but plastic sheeting and other commercial products can also be used.