Saving your own seeds

What to understand before starting

• Open-pollinated or peasant varieties (no F1, stated on the packet).
• Basic knowledge of crossing (self-pollinating vs cross-pollinating).
• Paper envelopes, packets, labels, a cool dry place for storage.

Detailed steps

1. Step 1

   Choose reproducible varieties

   Open-pollinated, peasant, or old varieties. Avoid F1 (unpredictable results), commercial hybrids.

2. Step 2

   Select the seed plants

   From the start, mark the 3 to 5 finest plants (healthy, vigorous, early, true to type). Never harvest from a single plant: loss of genetic diversity. Choose them in the conditions you really grow in: the farmer and seed producer Pascal Poot, in the Hérault, waters his tomatoes only at planting and saves his seeds from the plants that held out (Rue89, 2015; AFP, 2022). According to Nadia Bertin, research director at INRAE, this 'memory effect' does exist at the epigenetic level, but the yield is no longer the same, and nothing yet proves it is a lever against drought (AFP, 2022).

3. Step 3

   Manage crossing

   Tomato, lettuce, bean, pea: self-pollinating, a few metres between two varieties are enough (3 to 6 m for lettuce, bean and pea, up to 15 m for tomato). Squash, maize, cabbage: cross-pollinating, two varieties of the same species cross; they need about 250 to 800 m between them, or else bag the flowers or pollinate by hand (Seed Savers Exchange, quoted by the University of Illinois).

4. Step 4

   Let it fully ripen

   Tomato: very ripe, almost overripe. Squash: well after harvest, the fruit emptied in autumn. Bean: pods dry on the plant. Lettuce: let it bolt, wait for the seed heads.

5. Step 5

   Extract the seeds

   Wet method (tomato, cucumber): press the pulp, let it ferment 2-3 days in a jar, rinse, dry. Dry method (bean, lettuce, squash): shell, winnow, sort.

6. Step 6

   Dry

   Spread on paper or a sieve for 1 to 2 weeks, out of direct sun, in a ventilated room. A well-dried seed snaps cleanly.

7. Step 7

   Store

   Paper packets (never airtight plastic) in an airtight box with a silica-gel sachet. Cool (10-15 °C), in the dark.

8. Step 8

   Label and test

   Variety + year + place of harvest. Test germination each spring (10 seeds on damp cotton, 7-14 days).

Concrete examples

• Beefsteak tomato: a few very ripe fruits, the pulp left to ferment 2 to 3 days, then the seeds rinsed and dried for a week.
• 'Tarbais' bean: let the pods of the finest plants dry on the plant, then shell them.
• Red kuri squash: the seeds of a fully ripe fruit, from a plant isolated from other varieties of the same species, washed then dried.

How long do seeds keep?

Kept dry and cool: about 4 years for tomato, squash and cabbage, 3 years for bean, pea and carrot, 2 years for leek and sweetcorn, and only 1 year for onion, parsnip and parsley (Colorado State University and University of Illinois). For the others, and for an old packet, the germination test decides.

Can I re-sow an F1?

Yes but the result is unpredictable and mixed. Do not expect the mother plant.

How do I avoid squash crossing?

Bag the female flowers before they open, hand-pollinate with a male flower of the same variety, close the bag again.