Soil is a mixture of organic matter with chemical components and inorganic matter like minerals. Identifying soil before planting a lawn or garden is important because it gives warning about any soil problems already in your garden. When designing a garden, knowing your soil can help you choose the best plants for your garden or adjust the soil so it meets the needs of the plants you want in your garden.
Soil identification is most thoroughly done by performing analysis on the soil to find out what its components are and how much of each component makes up the soil. Soil samples are taken by sampling one sliver or cylindrical portion of the soil, sampled to 6 to 8 inches deep, for every 1,000 square feet of a gardening area.
Once the samples are taken, mixed and dried, they are sent to an agricultural lab for analysis. Experienced gardeners can sometimes tell familiar soil types by identifying soil properties visually and by touch, but an agricultural analysis gives a more complete reading of the properties of the soil.
The process of identification of soils through soil analysis can take up to six weeks, so most gardeners plan ahead by testing soil one or two months before the planting season begins.
The identification of inorganic matter in soils is often organized by the size of the particles. Mineral particles can be either coarse or fine; coarse particles are those greater than 2 mm in diameter, while fine mineral particles are smaller than 2 mm in diameter. Categories of particle sizes in soil are commonly arranged into three categories: sand, silt and clay.
Soil is usually identified by the dominant components of the soil. Loamy soil is considered to be an even ratio of sand, silt, and clay. Soil that is mostly sand is known as sandy soil. Soil that is mostly silt is known as silty soil. Loamy soil is commonly considered an ideal type of soil ratio because it allows for a healthy amount of water retention and drainage while providing a soil base that hangs onto plant-friendly nutrients.
Basic soil test costs start at $9 per sample, but can cost up to $40 per sample for detailed analysis and identification of specific chemical and organic components of soil.