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FACTSHEETS
 

SEED SAVING

We're going to leave these hints on how you can save your own seeds for Seedy Sunday.
Planning

Establish in advance the polloination rerquirements of the chosen vegetable. Check that the variety is not an F1 hybrid (these will not come true to the original plant). Ensure that whatever precautions which are necessary to maintain the purity of the variety are taken.
Labelling
The plants and subsequently the seeds should be labelled and dated at all points of the process.
Selection
Grow in a block and use the centrally positioned plants for seed. Select the best plants and the ones which go to seed the last. The characteristics of these plants will be carried over to the next generation.
Respecting the plant's internal clock
Do not harvest the seed until the fruit is at maximum maturity. Remember that the plant will have an internal 'plan' for its seed dispersal. Try to understand and time your harvest accordingly. Immature seed is unlikely to be viable.
Vegetables which self-pollinate habitually and which are grown for their fruit or seed are easy to maintain:
Peas and French beans; leave the pods on the plants until they are dry.
Tomatoes: allow to ripen fully, then:
  • Cut the tomato open and remove the seeds onto kitchen paper with as little pulp/juice as possible, spreading out the seed to ensure that seedlings are adequately spaced
  • Leave on a warm sunny windowsill for at least two days to allow the seeds to dry
  • Store the seeds (still attached to the kitchen towel) in an envelope, in a domestic fridge
  • To germinate, place the kitchen towel/seeds in a seed tray under a quarter of an inch of potting compost and incubate in a heated propagator, on a warm windowsill, or in the greenhouse
Cleaning the seed in this manner means that it can be conveniently stored, and being attached to the kitchen towel you are less likely to lose your precious seed.
Vegetables which are easy but require isolation:
Broad beans and runner beans: select plants from the centre of the block; do not grow more than one variety at the same time, or isolate with a screen.
A little extra effort is needed with:
Lettuces: hand pick the seeds as they mature but before they fly away.
Curcurbits (cucumber, courgette, marrow, squash, pumpkin): hand-pollination is essential. Allow the fruits to ripen fully.
Vegetables which require time and effort:
Carrots, onions, brassicas: grown over two years. Must be isolated in a netting cage but grown in as large a block as possible. Flies must be introduced or hand pollination attempted. Carrots can be harvested in the autumn before the ground freezes, leafy tops cut to one inch, and stored at high humidity and near freezing temperatures. In mild areas carrots can be left in the ground under thick mulch.
Radish: as above, but grown over one year.
Seed cleaning
Ensure that seed is reasonably free of chaff and other debris. Follow fermentation procedure for tomatoes.
Drying
The water content of seeds must be reduced in order to ensure their longevity. They can be:
  • dried on a tray out of the sun
  • on newspaper, checking the paper regularly to ensure that it isn't holding the moisture
  • hung in paper bags or laid on screens in a well-aired position
Storage
To save seeds from one year to the next it is probably sufficient, having dried them, to keep them in an airtight container in a cool place. For long term storage, the best place is probably the freezer, but the fridge or a cool cellar are also acceptable. Again, use an airtight container, preferably a Kilner jar or similar or even film canisters. Plastic bags are not airtight, nor are sealable plastic boxes. If your seeds have been slowly and carefully dried, they should last 10 years in a freezer with little loss of vigour.
Recovery
When you want to remove seeds from storage, there are two rules to obey. One is to allow the jar and its contents to come to room temperature before opening it. If you do not do this water vapour in the air will condense out on the cold surfaces of the glass and the paper in which you have stored the seeds, ruining your efforts to keep the seeds dry. The other rule is to allow the seeds to rest for a few days at room temperature and normal humidity before sowing them. They will slowly absorb water during this period, and there is some evidence that allowing the seeds to recover slowly is less damaging than putting them straight into moist soil.

THE PROBLEM WITH BLIGHT

Don't worry, we all get potato blight on our maincrop spuds (even Cara which is supposed to be resistant). It's one of those unavoidable occurrences when we have a damp late spring/early summer. Even spraying with Bordeaux Mixture (just about permitted under organic practice) doesn't do much in a year like this. But do let us know if you did manage to avoid it.
Recognition: dark brown patches start at edge of leaves which show silvery white (spores) on the underside. It spreads to stems and entire foliage may collapse and rot.

Action: Bordeaux Mixture thoroughly applied from mid June every two weeks may delay or prevent attacks. Once you have identified an attack cut foliage off to prevent spores being washed from leaves into soil and onto tubers. Leave three weeks before harvesting, then dig thoroughly removing even the tiniest tubers. Burn or dustbin any affected tubers (with brown markings) as the disease is carried in affected spuds but most will be OK if you acted quickly. Haulm (or foliage) may be safely composted as the spores only survive on living plant tissue. Wait another three weeks before mulching soil.

Next year, buy new (preferably resistant) tubers and dig up any rogue plants growing from stray tubers. Early potatoes are usually harvested before blight starts. Maincrops slow to develop blight include Cara, Stirling, Teena, Torridon, Remarka and Romano. There is more than one strain of blight, however, and some of the above are only resistant to a few. Alternating rows of different resistant varieties is good practice, as is wide spacing of plants and rows. Earthing up spuds or deeply mulching helps to prevent spores washing down to tubers.

Tomatoes (same family as spuds) will show the same symptoms and the disease will be passed on in infected fruits so bin all fruits and search ground carefully for any that have dropped. Haulm may be composted. Don't save seeds even if fruit (many will be edible) seem ok and dig up any self set plants next year. Less likely under cover, but I got it in my polytunnel this year!

Ruth Urbanowicz

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