Germination Testing for Saved Seeds
Test the viability of your saved seeds before the planting season. Knowing your germination rate helps you plan how many seeds to sow and whether a seed lot is still worth keeping.
Version History
Version 1.0 Current
Effective: 2026-03-24Initial version
Procedure Details
No hazards. Keep test containers away from direct sunlight and extreme heat.
You will need:
- Seeds to test (at least 10, ideally 20+ for a reliable percentage)
- Paper towel or cotton wool
- Sealable plastic bag or container with lid
- Spray bottle with water
- Label and pen
- Warm spot (20-25°C is ideal for most vegetable seeds)
Procedure Steps (Version 1.0)
Count out a known number of seeds — 10 or 20 makes percentage calculation easy. Record the variety, seed lot, age, and storage conditions.
Dampen a paper towel or piece of cotton wool. It should be moist but not dripping.
Spread the seeds evenly on the damp towel, leaving space between each seed.
Fold the towel over the seeds (or place a second damp towel on top). Place in a sealable plastic bag or container.
Label with variety name, number of seeds, and start date.
Place in a warm location (20-25°C). A kitchen bench or on top of a warm appliance works well. Avoid direct sunlight.
Check daily. Mist with water if the towel is drying out. It must stay consistently moist.
Count germinated seeds (radicle visible) every 2-3 days. Record the count and date each time.
After the expected germination period (check seed packet or reference — usually 7-14 days for most vegetables), calculate your germination rate: (germinated / total) x 100.
Record the final germination rate in your seed library. Above 80% is excellent. 50-80% is usable (sow extra). Below 50% — consider replacing the seed lot.
Germinated seeds with strong roots can be carefully transplanted into soil if desired.