The Jar Test: Soil Texture Analysis

The jar test is a simple soil analysis technique that helps determine the proportions of sand, silt, and clay in a soil sample. By shaking soil with water and allowing the particles to settle, you can visually analyze soil texture and apply the results to gardening, farming, or permaculture practices.

1. Collect soil samples from about 6 inches below the surface, removing rocks, roots, and debris.
2. Fill a clear glass jar about one-third full with soil.
3. Add water to near the top of the jar, leaving some space.
4. Secure the lid and shake the jar vigorously for 60 seconds.
5. Place the jar on a flat surface and allow it to settle undisturbed for 1–3 days until the water clears.
6. Observe the layers that form: sand settles first (minutes), silt settles next (hours), and clay remains suspended the longest (1+ day).
7. Use a ruler to measure the thickness of each layer and calculate percentages of sand, silt, and clay.
8. Use a soil texture triangle to classify the soil type (e.g., sandy, silty, clay, or loam).

Testing Soil Texture - Mason Jar Soil Test - Growit Buildit:

The Jar Test - Decoding your Soil's Texture - Milkwood:

📄 The Jar Test: A Simple DIY Soil Texture Analysis - Building a Food Forest: https://buildingafoodforestscotland.com/2025/03/29/the-jar-test-a-simple-diy-soil-texture-analysis/

• Compare soil samples from different garden beds, fields, or natural locations.
• Use distilled water instead of filtered water for more accurate results.
• Perform the test with added organic matter to see how soil composition changes.

• Wash hands thoroughly after handling soil.
• Use clean jars to prevent contamination.
• Keep jars sealed during shaking to avoid spills.

• Why does sand settle faster than silt and clay? (Sand particles are larger and heavier.)
• How does soil texture affect plant growth? (It influences water retention, aeration, and nutrient availability.)
• Which soil type holds nutrients the best? (Clay, because it has a high surface area and cation exchange capacity.)
• Which soil type drains the fastest? (Sandy soils, due to large pore spaces between particles.)
• Why is loam often considered the best soil for gardening? (It balances drainage, aeration, and nutrient retention.)