Growing your own vegetables used to mean growing your own seed as well, and for some of
us, it still does! Add an extra dimension to your gardening, by following plants
through generations from seed to seed. There are many other benefits to this
activity, too, such as the beautiful flowers that vegetables like carrots and leeks
produce, and the stately seed heads that follow look good in any flower border.
These flowers also attract useful insects into the vegetable garden, drawn by the supplies
of pollen and nectar. If you deliberately grow a lot of pulses to produce seed, not
only will you have a supply for next year, but also a high protein vegetable that can
easily be stored for use in the winter - why not grow your own chilli beans, haricots and
dried peas? Some crops produce so much seed, that you can let them scatter a
proportion of it naturally in the garden, where it will germinate and provide you with
more plants for absolutely no effort whatsoever. Some years you dont have to
sow a single lettuce or spinach seed at all! Some
modern varieties are protected by Plant Breeders Rights or patents, which mean that it is
illegal to save seed from them, unless you pay the breeder royalties or get
permission. This is an important ruling which ensures that the very expensive
business of producing improved varieties is not lost to commercial competitors or farmers
who save seed themselves and possibly sell it or regrow the variety, with no benefit going
back to the breeder. Many modern varieties are further protected through the use of
F1 hybrids, which means the seed packet you buy contains the seed from a cross between two
breeding lines, and if you produce seed from these it will contain an often unsuccessful
mixture of the two different types. Old varieties, however, become public
domain after a period of usually 25 years, and are free to use. Because of this,
there is pressure from breeders to eliminate these old varieties, which no longer make
them any money, and to encourage the use of new improved varieties. Every year,
before a variety can be sold, it has to be registered on the national list of recommended
varieties, which is a way of controlling the quality and authenticity of seed sold, but is
also expensive enough to discourage the sale of seed of vegetables that do not have a mass
market. This means that old varieties which suit the home gardener but not the
commercial producer are deleted from the list and are no longer available. For
example, tall pea varieties that you can pick without bending, and produce masses of peas
through the summer, are no good if you want to harvest with a combine the moment the whole
field reaches perfection, so the gardener is left with a choice of dwarf, leafless
varieties good for freezing - and whats the point in growing frozen peas?
Of course, like everything in
gardening, its not always straightforward, and some vegetables give more problems
than others. A few simple guidelines should help to get you started. See over
the page for nine handy hints.
Successful seed saving
- Always choose varieties that are true breeding, not
F1 or mixtures, and these should be old varieties.
- The easiest vegetables to save are the ones that
self pollinate before the flower is fully open, so that without taking any precautions you
can be sure of the seed coming true next year: Lettuce; Peas; Tomatoes; French beans
- Some vegetables have not been bred to a high degree,
and there are no real varieties as such, so nothing can go wrong if you grow a few to
seed: Rocket; Land cress; Sorrel; Corn salad - these all establish themselves naturally in
the garden, a bit like having edible weeds!
- The next easiest sorts are the ones which produce
lots of seed from a single pollination, so that you only have to protect one or two
flowers against stray pollen, and perform a single hand pollination. You also get to
eat the fruit with most of these, so you dont lose any crop! Pumpkin,
Courgette, Melon, Cucumber (Ridge varieties are best - dont eat the
greenhouse varieties that you normally prevent from pollination, avoid F1 and all-female
varieties). These cucurbits have separate male and female flowers on the
same plant, which need to be protected from insects before they open. When they
open, take a male flower (no sign of the fruit behind it) and introduce it to the female
(small swelling at the back of the flower is the deveopling fruit). Peppers and
Aubergine just need to be protected from stray pollen (OK in a greenhouse), and make sure
the pollen on the flower gets onto the stigma by using a feather or paintbrush (leave till
seeds are ripe - dont eat the old aubergine!).
- The trickiest category have lots of flowers, each
producing only one or a few seed, and requiring cross-pollination with another plant for
success. These must be grown as a block of plants of the same variety, to ensure
pollination and maintain inherent diversity, but they must be protected against
pollination from nearby plants of the same or related species. For some crops, the
distance that counts as nearby is as much as a mile, because pollen can be brought by bees
or the wind. These need to be screened from other sources of pollen - e.g., in a
polythene cage, but insects or wind must have access to ensure pollination occurs within
the cage! Insect pollinated: Brasssicas, e.g. cabbage, sprouts, broccoli,
kale, cauliflower; some other Crucifers, e.g. radish, turnip, oriental vegetables like Pak
Choi; Carrot family, e.g. parsnip, parsley; Onion family, e.g. leek; Runner beans; Broad
beans - these two beans do not need so much distance - 100 metres or
so. Wind pollinated: Spinach; Beetroot;
Sweetcorn.
- Once the plants have pollinated, and seed have set,
leave them alone to ripen and/or dry on the plant. Some will need a bit of support,
as the seed heads may be quite heavy on long stems. Tomato and cucumber seed need to
be removed from the ripe fruit, washed in dilute bleach to remove the jelly, washed in a
sieve and then dried on blotting paper. Brassicas and Crucifers, as well as peas and
beans, should be shelled from the dried pods, and checked for any infestations of grubs
which sometimes occur. Loose seed heads like carrots and onions can be stored whole
in paper bags to dry fully, then threshed to release the seed into the bag.
- Once extracted and dried, all seed should be stored
in packets or jars, in a cool, dry place.
- Always make sure that you collect seed from healthy,
typical individuals of the variety you want to keep, and observe the plants that grow from
them to make sure you havent had any outpollinations, mix-ups or disease
problems. Some viruses in particular are seed-borne, and so for things like
tomatoes, it is worth getting new sources of seed every few years.
- If youre really keen, why not join the
Heritage Seed Library of HDRA, which gives access to
old forgotten varieties, lots of information on seed saving, and allows you to swap your
seed with that of other savers. At least pass on a few of your surplus supplies to
friends, as most vegetables produce far more seed than you need, and of course it
doesnt keep for ever.
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