According to it’s composition a soil is classified as ‘sandy’, ‘loamy’ or ‘clayey’.
- Sandy soil shows great aeration and drainage, dries out quickly, it’s often poor because it doesn’t keep nutrients well and doesn’t break down easily to offer new nutrients
- Loamy soil shows good balance between aeration and drainage, has good water retention, keeps nutrients and breaks down into nutrients.
- Clayey soil is heavy, doesn’t drain well, plants get waterlogged, nutrient rich
Take a handful of soil from your garden (moist but not wet), give it a firm squeeze and check the resulting bolus. Also try to roll it between two hands to form a ribbon.
| no coherence, no ribbon, grains stick to your fingers | Sand |
| fragile bolus, no more than 5 mm ribbon | Loamy sand |
| fragile bolus, sticky when wet, grains stick to your fingers, clay stains on fingers, up to 15 mm ribbon |
Clayey sand |
| fragile bolus, sand grains visible, up to 25 mm ribbon | Sandy loam |
| coherent bolus, spongy, no obvious sand, up to 25 mm ribbon, may feel greasy if much organic matter is present |
Loam |
| coherent but will crumble, very smooth and silky, 25 mm ribbon | Silty loam |
| strongly coherent bolus, sand grains, 25 to 40 cm ribbon | Sandy clay loam |
| coherent bolus, spongy feel, plastic when squeezed, smooth to manipulate, 40 to 50 cm ribbon |
Clay loam |
| plastic bolus, sand grains, 50 to 75 mm ribbon | Sandy clay |
| smooth plastic bolus, 50 to 75 mm ribbon | Light clay |
| smooth plastic bolus, like plasticine, 50 to 75 mm ribbon | Medium clay |
| smooth plastic bolus, like stiff plasticine, at least 75 mm ribbon | Heavy clay |