Water is a one of our most important resources and we need to be responsible in how we use it. Knowing your soil type will help to determine the amount and frequency of water needed to successfully grow plants.
To determine whether your soil is sand, clay or silt, rub some moist soil between your fingers and if it feels gritty, it is probably sand. If it feels sticky, it is most likely clay. If it feels smooth it is silt. Another test would be to squeeze a moistened ball of soil and if it breaks with slight pressure that would indicate sandy soil. If it stays together but changes shape easily, that would indicate more of a clay soil. Note that soils often are a mix of different types and may not exactly follow these general guidelines. For example, a sandy soil that contains some clay will hold more water than pure sand.
It is best to water heavy clay soils slowly and infrequently. Because clay-type soils take in water slowly, applying too much water at once causes runoff. Once clay soils are wet, they hold water for relatively long periods.
Sandy soils absorb water quickly and drain quickly. Applying large amounts of water to sandy soil causes it to drain into subsoil layers beyond the reach of plant roots. Sandy soils don’t store much moisture for plant growth, so they require light, frequent watering.
Well-drained mountain soils act very much like sandy soils, so water lightly and frequently.
For more information, see the following Colorado State University Extension fact sheets.
- Drip Irrigation for Home gardens
- Micro-Sprinkler Irrigation for Orchards
- Lawn Care
- Vegetable garden: Soil Management and Fertilization