Define soil texture and describe associated characteristics.

Define the term ‘soil texture’. Particle sizes of stones, sand, silt, clay (using Soil Survey England and Wales classification).

SOIL TEXTURE

Soil texture is defined as the relative amounts of sand, silt and clay particles present in a sample (by %). This gives a name to a soil. Soil scientists recognise 17 names or more types of mineral soil textures. However for gardeners there are 8 basic types: Sand; Loamy sand; Sandy loam; Medium loam; Silty loam; Clay; Sandy clay; Clay loam. Some use the term “the feel of the soil”.

Soil texture determines the soil potential: Workability; Field capacity (water holding); Food holding capacity (clay buffering effect); Drainage potential; Warmth and earliness of plant growth and cropping; And so its use.

Soil particles in a soil crumb

Describe the characteristics of the following soils: sandy loam, silty loam and clay loam: feel (gritty, silky, sticky/hard), nutrients, water retention, temperature.

SAND (SOIL) Basic garden soil type

LOAMY SAND (SOIL) Basic garden soil type

SANDY LOAM (SOIL) Basic garden soil type Sand 60%; Silt 20%; Clay 20%. A light soil – free-draining, gritty, warms up quickly in spring, good for early crops, fertility can leach away - needs feeding and irrigating. Can be worked in wide range of weathers.

MEDIUM LOAM (SOIL) Basic garden soil type

SILTY LOAM (SOIL) Basic garden soil type Sand 20%; Silt 50%; Clay 30%. A sticky feel when hand tested. Heavy (not so easily worked as clay that will respond to weathering and liming). Wet in winter, no buffering effect. Bakes hard in summer. Limited period for working/cultivating

CLAY (SOIL) Basic garden soil type

SANDY CLAY (SOIL) Basic garden soil type

CLAY LOAM (SOIL) Basic garden soil type Sand 20%; Silt 40%; Clay 40%. Smooth silky feel when hand tested. Heavy soil. Wet in winter/clod/late. Good colloidal activity making nutrient-rich. Good water-retention, though cracking in summer.