Seed Saving |
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Why save seed
To not save seeds is to be reliant on seed companies and to miss an opportunity to get lots of free seed. Whats more saved seeds are adapting to the local growing conditions, which will make crops more productive and resistant to pests and diseases.
By some simple selection for desirable traits we can help this process along, creating our own locally adapted vegetable varieties. Seed saving by gardeners is also the only way most rare and heritage varieties can be kept from extinction.
How to save seed
Select seed from plants with characteristics you like and that grow well and quickly in your conditions. But dont collect from only one plant, you will be breeding out diversity and the ability of the crop to adapt.
Not all seed collected will necessarily produce offspring that are true to type, that is share the good characteristics of the parent plant.
Seed saved from F1 hybrid varieties will not produce plants like the parent plant. Choose only non-hybrid seeds, known as open pollinated.
Plants from the same species can cross with each other producing mixes of the parent plant. Although this can be a good thing if you are trying to breed a new variety, often this must be avoided it can destroy the useful original traits in distinct crops. In order to avoid crossing it is necessary to know a little about how plants reproduce. Unlike animals most plants have organs of both sexes. These are located sometimes in the same and sometimes in different flowers. The male portion of the flower produces pollen. These tiny grains have to pass onto the female part of the flower that is receptive to pollen, known as the stigma, in order for a fertile seeds to be produced. This process is called pollination. In order to avoid unwanted crossing and to produce viable seed, pollen from a variety must reach and pollinate the female flowers of that plant, while pollen from other varieties must be prevented from reaching the stigma. This can be done in one of four ways:
Which methods are suitable depends on the type of pollination. Plants are pollinated in three differing ways, by wind, insects or by what is known as self-pollination. The self-pollinated crops are most tomatoes, beans, lettuces, peppers and aubegines. These are by far the easiest to save true to type seed from, because the pollen is transferred directly to the stigma within the flower. With beans all that is generally required is to separate crops by a few feet to avoid pollen being transferred to an adjacent variety. Insects may occasionally pollinate some of the self-pollinated crops such as peppers. Insects pollinate most crops, an isolation distance of a few hundred feet is generally sufficient to avoid almost all crossing between compatible plants flowering at the same time. It is possible to grow more than one insect-pollinated crop much closer together and avoid cross pollination using physical barriers and distractions to help keep insects from visiting both varieties. Aleta Anderson from a Washington based seed saving group, explains ‘Barriers, hedgerows and lots or nectar-bearing plants are important parts of maintaining isolation. If there’s plenty of nectar to choose from insects are more likely to stay in the place they are in, enjoying lunch from the bounty they have… We use these techniques regularly and have found them to be successful’. Wind pollinated crops are corn (maize), spinach, amaranths, beets and Swiss chard, these are the most difficult to prevent from crossing. There must be no other varieties within at the very least a 1/4 of a mile, depending on wind direction, shedding pollen at the same time. If there is, some of the harvested seed will result from a cross between these two varieties. The closer the varieties are located, the higher the amount of crossed seeds. What can form crosses? Squashes, pumpkins and marrow are from 4 different species of cucurbit, except where noted types of each species will only cross with each other. All of species Cucurbita pepo = Courgette/ Zucchini, Marrow, Squash varieties-inc. Spaghetti, Acorn, Scallops, Crooknecks, Cocozelles. Mature plants have prickly leaves and stems; seeds are small and white. All of species Cucurbita maxima = Common Pumpkin and Winter Squash varieties- inc. Buttercup, Hubbard, Banana, Turks Turban. Most cold hardy species, seeds are thick, yellow and have a plastic-like coating. All of species Cucurbita moschata = Squash varieties inc. Butternut, all Cheeses, Distinguishable by white patches on leaves. Cucurbita mixta = Squash varieties inc. Green striped cushaw. Plants similar to in appearance to C. pepo, and may sometimes form crosses with that species. Seeds are grey. All of species Brassica oleracea = Cabbage, Broccoli, Cauliflower, Kale, Brussels sprouts, Kohl-Rabi All of species Brassica rapa = Turnip, Chinese and Asian cabbages inc. Pak-Choi, Mizuna, Mustard-spinach Members of the brassica families Brassica rapa, B. napus (rape, swede/ ratabaga) and B. junecea (Indian and oriental mustards, leaf mustard) have been known to make fertile crosses with each other All of species Beta vulgaris = Beetroot, Swiss chard, Sugar beet, Fodder beet/ Mangel Both of species Cynara cardunculus = Cardoon and Globe Artichoke Both of species Lactuca sativa = Lettuce and Celtuce (Stem lettuce, Asparagus lettuce) Endive and escarole, Cichorium endiva, can pollinate Chicory, Cichorium intybus, however endive itself is self-pollinating and cannot be can pollinated by chicory. Wild relatives Collecting Seeds All seed collecting is best done during dry weather. Crops that produce their seed in pods: Crops that produce seed inside fruits Seeds borne on top of a flower stalk Small seeds are winnowed to remove the unwanted plant debris, or chaff. This can be done by pouring into a container in a breeze that carries off the chaff and dust, or through an appropriately sized sreeen or sieve. Storing Seeds Paper and cloth bags are adequate storage materials in a dry place. Airtight glass jars can help protect against humidity and rodents. Peas and beans and other large seeds with moist fleshy insides store best in breathable containers. A refrigerator is an excellent place to store seeds. Seeds are alive; they metabolize even in their dormant state and gradually use up their carbohydrate reserves. While some vegetable seed can remain viable in storage for as long as 15 years or more, and grains may remain viable much longer under stable environmental conditions, every year in storage will decrease the amount of seed that will germinate. Seed is best sown the following year after being collected. Seed Exchanges
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