Know Your Soil
Soil is the foundation for all plant life, providing plants with water and nutrients needed for growth. Soil is made up of weathered rocks and minerals and organic materials (such as plant material). Organic materials provide soil structure by holding the rock and mineral particles together.
Soil is classified by its texture type. Texture is determined by the relative proportions of sand, silt, and clay in the soil.
Soil texture types:
- Coarse Sand (0.2mm – 2.0mm) & Fine Sand (0.02mm - 0.2mm): Sand is the largest soil particle. It contains fewer, larger pore spaces between particles which allow water to drain rapidly, without giving plant roots a chance to absorb water and nutrients.
- Silt (0.002mm – 0.02mm): Silt contains medium sized particles and pore spaces which retain water for plants to use, while also allowing for adequate drainage.
- Clay (<0.002mm): Clay is the smallest soil particle and contains many small pore spaces which limit the amount of water and nutrients available to the plant. These small pore spaces decrease water infiltration and “hold on” to water and nutrients, making it difficult for plants to absorb them.
- Loam: Combination of sand, silt, and clay. Ideal texture for optimum water retention, drainage, plant growth and soil health.
Soil particle size comparison
Finding your soil texture type:
Soil texture triangle
Once you know your soil type, you can determine which soil amendments are best for your lawn.
Soil amendments are made of organic material and can improve soil texture and structure.
In sandy soils, amendments increase lateral movement of water in soil, providing plants with an opportunity to absorb water and nutrients before the water drains below the root zone.
In clayey soils, amendments increase infiltration and drainage, bringing water and nutrients into the root zone for plant use.
Soil with good structure and texture
Decomposed organic material that improves the texture and structure of all soil types. Compost also improves nutrient availability and soil aeration (air in the soil available to plants for growth).
Types of compost:
Humus – decayed organic matter such as leaves and other plant material
Mushroom compost – mixture of straw, peat moss, and other organic compounds
Topsoil – partially decomposed compost
Sphagnum peat moss and peat moss – Very absorbent, dried moss which allows air and water to infiltrate and remain in the soil. It also improves water retention by absorbing water and slowly releasing it for plant use, as well as loosens compacted soil.
Coco coir – Absorbent coconut fiber from coconut husks that allows air and water to infiltrate and remain in the soil. It improves water retention by absorbing water and slowly releasing it for plant use, as well as loosens compacted soil.
Perlite – Volcanic glass which increases infiltration rates and soil aeration.
Know your soil and maintain healthy soil to encourage plant growth, conserve water, and reduce runoff - keeping our streams and community clean!