Sirius Acres · @siriusacres

Mason jar soil layer calculator

After your jar settles, measure each band. This turns heights into sand / silt / clay percentages and compares them to a practical ~40 / 40 / 20 loam target.

Quick reminder

  1. Jar one-third soil, nearly full of water; shake hard; leave overnight.
  2. Sand settles first (bottom), silt next, clay on top once the water clears.
  3. Measure each layer’s height with a ruler (same units). Enter them below.

Layer heights

Total settled soil: —

Your jar
(schematic)

Your soil mix vs loam

Sand
—
target 40%
Silt
—
target 40%
Clay
—
target 20%

—

A jar test is diagnosis, not a lab assay. Organic matter, gravel, and incomplete settling skew the bands. Treat ±5 percentage points as “close enough” for backyard beds — then compost on purpose instead of guessing with miracle bags.

Next step: Download the free Suburban Soil Fix Sheet (PDF) — jar % → what to add this weekend. No email wall.

See the full backyard system →