Test saved seed before spending water on a bed

A simple germination test helps decide whether a saved seed lot is worth sowing. It can reveal a weak lot before you spend scarce water, compost and bed space on it. It does not certify freedom from disease or guarantee field emergence.

Take a representative sample

Extension seed-testing guidance uses a counted sample on a moist paper towel. Select seed without choosing only the largest or best-looking examples. For a household check, 20 seeds gives a rough indication; precious small lots may need a smaller sample and a more cautious interpretation.

Run and label the test

1. Write the crop, variety if known, harvest year and test date on the label.
2. Place the counted seeds on clean damp paper, keeping them moist but not submerged.
3. Maintain conditions suitable for that crop and inspect regularly for normal seedlings and mould.
4. Allow the crop’s expected germination period, then record normal seedlings, failed seed and any uncertainty.

Calculate clearly

If 16 of 20 seeds produce normal seedlings, the observed germination is 80%. That is a small-sample result, not a laboratory certificate. For 40 intended plants, 40 ÷ 0.8 gives 50 seeds before allowing for field losses. Do not simply add 20% and assume the arithmetic guarantees 40 plants.

Use the result sensibly

Keep a useful lot cool, dry and labelled. A poor result may justify retesting under better conditions or replacing the seed rather than sowing much more into a water-limited bed. Share the test date and result when exchanging seed, and keep suspect or mouldy lots separate.

Namibian climate and microclimate

Heat and humidity in storage can affect viability, and paper can dry quickly during a test. A good indoor result still needs suitable sowing depth, soil temperature and moisture outdoors. Compare subsequent field emergence with your test.