The key to gardening often lies in understanding the soils used for plants. According to Department of Environment and Resource Management in Australia, plants obtain the majority of their nutrients from soil. Most gardeners learn about the soil texture and soil pH to determine what to add to their gardens and landscapes. It is imperative to understand these factors for the best plant growth.
Clay soil is dense and compact. It absorbs and holds both water and nutrients. Plants that thrive in wet environments do well with clay soils. But plants that are prone to root rot or flourish in dry environments will soon die in clay soils. Gardeners can add pumice, small rocks or coarse organic matter to reduce the density of clay soil.
Clay soil is 50 percent or higher density of clay with a small volume of sand or silt. The average PH balance of clay soil is slightly acidic due to the high percentage of rainwater that naturally occurs in this soil type.
Sandy soil has large, loose granular particles. Sandy soils are alkaline in pH due to the lack of nutrient absorption. Sandy soil often requires the addition of compact organic matter to increase the density. Sandy soil allows drainage that is frequently accompanied by nutrient loss. Slow-growing, non-blooming plants that require dry soil do best in sandy soil types. This type of soil cannot naturally sustain fast plant growth rates or additional nutrients for bloom and fruit yields.
According to the NDSU Agriculture Department, silt soil contains material that is medium-sized particles, larger than clay and smaller than sand. Silt is typically found in sediment parts of the soil. Gardeners adjust the soil texture and pH to meet specific types of plants by converting it to either higher or lower density. For example, gardeners might add clay to silt soil for plants needing high amounts of water.