Types of Soil Grains

Plant growth and fertility is much affected by the texture of the soil. The definition of soil texture refers to how fine or coarse and the soil’s mineral is. A good soil texture will provide a good fertility and growth because it affects the air circulation and nutrient retention within the soil. All soils contain clay, sand and silt, but in different proportions. Soil texture testing is made by rubbing a small soil between the forefinger and thumb. Here are some of the types of soil grains.

Types of Soil Grains

  • Loamy soil is a soil with contents of 40 percent sand, 20 percent clay and 40 percent humus. It has a granular structure, gritty and loose texture. Although loamy soil retains moisture, but it still drains well which makes it suitable for gardening. To improve the structure and the texture of loamy soils, add compost or other organic matter, which could provide plant’s needed nutrients.
  • Sandy soil can be recognized by the gritty feel with large particles of minerals and rocks. This soil has grainy structure that does not hold well together, which makes the nutrients leached out from the soil quickly. To decrease the soil nutrients leaching from the soil, add peat moss to bind the sandy soils.
  • Clay soil textures are slick and slippery as it is high in clay content. The high clay content compact easily, the soil particles binding prevent air circulation, proper drainage and root growth. By adding peat moss, the clay soils break down easily as the peat moss helps by aerating them.
  • Silty soil has greasy feel and feels like rubbing baby oil when rubbed between your fingers. With it’s high in humus content, silty soil is one of the most fertile types of soil. It has color of dark sand and smooth texture. Silt is made from fine organic particles and minerals that help provide a better drainage and has increased nutrient retention than sand.

Image Credit:

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Additional Reading:

Stored-grain Ecosystems (Books in Soils, Plants, and the Environment)

Soil Science: Step-by-Step Field Analysis