Germination Rate Calculator

Calculate viable seed count from germination test results. Determine if seed meets planting standards.

Results

Visualization

How It Works

Germination rate is the percentage of seeds that produce normal, healthy seedlings under ideal conditions. Pure Live Seed (PLS) combines germination and purity to give the true viable seed percentage. Seed must test ≥80% germination to be sold commercially in most states.

The Formula

Germination Rate = (Normal Seedlings ÷ Total Tested) × 100
PLS = (Germination% × Purity%) ÷ 100
Seeds Needed/Acre = Target Population ÷ PLS

Variables

  • Normal Seedlings — Seedlings with healthy root and shoot development
  • PLS — Pure Live Seed — combines germination and purity into one number
  • Purity — Percentage of seed lot that is the intended crop seed (vs weed seed, inert matter)

Example

92 out of 100 seeds germinate with 99% purity: PLS = (92% × 99%) = 91.1%. To get 34,000 plants/acre, plant 37,322 seeds/acre.

Tips

  • Run a warm germination test 6-8 weeks before planting for carry-over seed.
  • Cold germination tests better predict field emergence than warm tests.
  • Seed stored below 50°F and 50% humidity retains viability longest.
  • Soybean germination drops fastest — test annually for carry-over seed.

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