Emily Hartley
Why save your own seed?
There is something quietly satisfying about sowing a row of beans in May from a handful of seeds you dried on the kitchen windowsill last autumn. Saving seed costs almost nothing, ties you to the rhythm of the plot, and — most importantly — keeps the varieties you actually like in circulation. A tomato that crops well on your particular soil, shrugs off a wet summer and tastes of something other than water is worth keeping. Commercial seed is often grown abroad and can vary from year to year; your own seed is already adapted to your conditions.
The other reason is generosity. Once you have saved seed, you have something to swap on the allotment site, drop into the communal seed box, or press into the hands of a nervous new plot holder. It is the oldest kind of sharing there is.
Know what will come true
Before you save anything, check whether the variety is open-pollinated (often sold as heritage or heirloom) or an F1 hybrid. Open-pollinated varieties breed true, so their seed produces plants much like the parent. F1 hybrids, bred by crossing two specific parents, will not — their offspring are a mixed bag, often disappointing and rarely worth the space. So skip saving seed from F1s and choose named open-pollinated varieties instead.
Choose plants, not just fruit. Look for the strongest, healthiest individuals: first to crop, best flavour, best resistance to whatever your plot throws at them. Never save seed from a sickly plant, however good the fruit tasted — you would be selecting for weakness. For beans and peas, save from at least half a dozen plants to keep genetic diversity.
Beans and peas: the easiest place to start
If you have never saved seed before, start here. French beans, runner beans and peas are close to foolproof.
- Leave a few pods on your best plants at the end of the season and stop picking them. They will swell and turn brown or parchment-coloured.
- Pick the pods on a dry, sunny day, once they rattle when you shake them. If rain is forecast, pull the whole plant and hang it upside down somewhere airy indoors to finish.
- Shell the pods by hand and discard any seed that is mouldy, shrivelled, or has a neat round hole in it — that is bean weevil.
- Test a few by pressing with a fingernail. If the seed dents, it needs longer to dry. If it snaps, it is ready.
- Runner beans cross-pollinate freely with other runners nearby, so growing several varieties means you may get crosses. French beans are largely self-pollinating and much safer.
Tomatoes: ferment before you dry
Tomato seed sits inside a gel sac that stops it germinating within the fruit, and that gel can carry disease. Fermenting removes both problems.
- Pick a fully ripe fruit from your best plant — chosen for flavour and health rather than sheer size.
- Scoop the seeds and gel into a small jar, add a splash of water, and leave it on a warm windowsill for three to five days, stirring once a day.
- A layer of mould will form on the surface and the good seeds will sink. Pour off the mould and any floating seeds, then rinse the rest in a fine sieve.
- Spread the seeds thinly on a coffee filter or sheet of kitchen paper and dry them out of direct sun for a fortnight, until they snap rather than bend.
Only ever save from healthy plants: tomato seed can carry blight and mosaic virus from one year to the next.
Flowers for free colour
Flowers are generous seed producers, and many are child's play to save.
- Calendula (pot marigold): let the flower heads turn brown and papery on the plant, then rub the curved seeds out between your fingers.
- Nasturtium: the fat, wrinkled seeds form where the flowers were. Pick them brown and dry; the green ones are lovely pickled like capers.
- Sweet peas: let the pods dry on the vine, but check daily — they shatter and fling seed everywhere. Slip a paper bag over the pods if you are worried.
- Poppies and foxgloves: tip the dried seed heads upside down into a paper bag and shake. Foxgloves cross-pollinate readily, so the seedlings may not match the parent exactly.
Drying, labelling and storing
Whatever you save, it must be bone dry before it goes into storage. Damp seed develops mould and dies. Leave it in an open paper envelope in a warm, airy room for a week or two — not on a radiator, which cooks it.
Label everything straight away, because dried seed all looks the same by February. Write the variety, the year, and a short note — "tall, late, superb flavour" — on the envelope. Then store in a cool, dark, dry place. A tin or jar with a sachet of silica gel is ideal for long keeping; the fridge works well too, provided the container is properly sealed against moisture.
Most seed stays viable for years: beans and peas three to five, tomatoes four to six or more, calendula two or three. Test a few on damp kitchen paper before sowing and you will know exactly what you have — and exactly what to share.
