Plant health depends primarily on soil quality, which is determined by both fertility and texture. Soil is a combination of organic and mineral matter. There are three main types of soils: clay (heavy), loam (medium) and sand (light).
Clay has minute, flat particles that compact together easily, and although they do not drain well, they usually have good nutritive value. Clay has a silky, slick texture.
Loam is a mixture of clay, silts and sand particles and is considered an ideal soil since it drains well but can also retain moisture. Loam has an ideal crumbly texture that holds together well but also allows air and water through.
Sand has large, rounded particles that drain quickly and get warm quickly. It has a coarse texture.
Less than ideal soils can be improved by the addition of organic matter; add lots, dig in deeply and mix well. Clay soils: organic matter increases aeration and improves drainage. Sandy soils: organic matter holds nutrients and water and improves fertility.
If you have good soil texture but your plants are not doing well, consider a soil analysis. It will indicate the condition of the soil and its nutrient status. Once you have the results you can make an effective plan to correct any deficiencies. Do your own simplified analysis with a kit purchased from your local garden center, or ask their staff where you can get a complete professional analysis done.
Ongoing methods can be used to improve and maintain soil health:
- organic amendments: improve soil quality and fertility; they include peat, compost, rotted manure, seaweed, leaf mold
- mulching: improves moisture retention, nutrient value
- crop rotation: avoids mineral depletion
- soil builders: improve fertility; cover crops like clover, fall rye and other “green manures,” peas, beans
- pH balancing: improves nutrient availability (do only if indicated by a soil test): for acidic soils (high rainfall areas) add dolomite lime; for alkaline soils (low rainfall areas) add peat moss or wood ash