Why Is Loam the Best Type of Soil?

Texture Test

• Soil, since it is composed of mineral particles, organic matter, air and water, runs through a great spectrum of textures. Find out your soil's texture by taking a damp piece of soil in your hand and squeezing it tightly. Upon release, loam soil separates into crumbly pieces. Clay soils retain your fist's shape. Sandy soils separate entirely.

Types and Quality

• Texture reveals a great deal about soil's potential for plant nourishment. Tightly packed clay soil's fail to provide air to root systems. These inhospitable environments do not facilitate microbial growth, which, in turn, limits nutrient processing. Clay soils are dense and saturated, limiting the root system's ability to take in water. Sandy soils, on the other hand, drain water so quickly that nutrients leach from the soil and water runs to quickly for adequate uptake. Loam soils, with their crumbly chunks, retain enough water for roots to absorb, provide enough air circulation for both roots and microorganisms, and retain nutrients.

Amendments

• Soil texture also determines a soil's pH balance. The pH scale is a way to measure a soil's acidity or alkalinity. Acidic soils tend to be dense and compacted. Nutrients are not easily broken down in these environments, causing different minerals and compounds to "lock." An increase in unavailable, or "locked," nutrients inhibits plant growth and increases a soil's acid levels. Low acid, or alkaline soils tend to the opposite extreme. These sandy, coarse soils are nutrient poor. Compost provides organic bulk that helps nourish sandy soils and helps aerate compacted soils. Other amendments like lime or granulated sulfur are added to soil to achieve a balance. Incorporate chemical soil amendments with caution and in accordance with soil test recommendations. University extension offices provide soil tests and recommendations.

Considerations

• Although loam is preferred by the majority of plants and crops, there are some exceptions. Cactus and succulents do best in light, alkaline soils. Rhododendrons and azaleas prefer acidic soils. The variety of plants is helpful to gardeners whose soil is not easily amended. Another option for those gardening in difficult soil is to create raised beds. Raised beds full of organic matter and garden soil allow clay soils a chance to drain. Sandy soils retain nutrients much better in well-maintained raised garden beds.