DIY soil tests: texture, drainage and the ribbon test
Three free soil tests you can do at home with a jar, a shovel and your hands: find your soil texture, how fast it drains, and what that means for watering and planting.
Three simple tests tell you most of what matters about your soil: what it’s made of (texture) and how fast water moves through it (drainage). Texture decides how often to water, how fast water soaks in, and how the soil behaves when you dig.
Jar test (texture)
- Fill a straight-sided jar about one-third with soil from root depth (pick out stones, roots and debris).
- Add water until the jar is about two-thirds full, plus a teaspoon of dishwasher detergent or salt-free water softener to separate the particles.
- Shake hard for 3–5 minutes, then set it down and start a timer.
- After 1 minute, mark the height of the settled layer: that’s the sand.
- After 2 hours, mark the height again: sand plus silt.
- After 2 days (when the water clears), mark the final height: everything, including clay.
Ribbon test (texture by feel)
Take a walnut-sized lump of soil, wet it until it’s like putty, and work it in your hand. Then press it between your thumb and finger, pushing it up into a ribbon until it breaks under its own weight.
Drainage (percolation) test
- Dig a hole about 12 in (30 cm) deep and 6–12 in wide.
- Fill it with water and let it drain completely. This wets the surrounding soil; skip it and the result will be too fast.
- Fill it again. Measure the water depth, wait a set time (an hour is easy), and measure again.
If the hole still holds water the next day, test again somewhere else and dig deeper to look for a dense or cemented layer. Drainage problems are usually about a layer below, not the soil you plant in.