Some quarter million known species of flowering plants require pollination. A seed or fruit is produced when pollen moves from the anther to a receptive stigma, this is called pollination.
Cross-pollination occurs when pollen is transferred from one compatible flower to another.
Self-pollination occurs when pollen comes from the same flower or plant or from a clone.
Plant propagation is an important aspect of gardening. With most plants sexual reproduction involving seeds has evolved as an efficient means of reproduction and sowing seed is the easiest and most natural method of propagation. However, plants may be propagated by cuttings, layering, division, budding/grafting or other vegetative means (asexually) as well.
Sowing seed is the easiest and most natural method of propagation and seeds may be saved from desirable plants or they are relatively inexpensive to purchase. They can be bought in large quantities and they are often treated to be disease free. Read the article on Open Pollinated Plants.
When propagating from seed you need to have viable seed, warmth, moisture and air. It's best to use fresh seed but some seeds will remain vital for years, longer if stored properly. Light, porous soil is the best medium to use when growing from seed as it contains air which is needed for new roots, however, seeds can be sprouted on a variety of mediums, such as moistened towelettes. Food is not needed for germination and for the most part neither is light.
The seeds contain within themselves enough food to grow (from the Cotyledons or seed leaves) until the first true leaves have formed (usually the 2nd pair of leaves), then they must draw nutrients from the soil.
If you save seed be aware that seeds from hybrid (F1) plants when sown will produce a variety of offspring, only some of which will be true to type. You may find it interesting to plant seed from hybrids as the offspring may vary considerably and you can decide which characteristics of the resultant plants you fancy (which taste better, which look more appealing, etc.). New varieties can come about in this way. Read the article on F1 Hybrids.
Cuttings from shoot or leaf are detached pieces of plants that are taken for the purpose of producing new plants and under the proper conditions they will root easily (not all will of course) and produce plants more quickly than seed. This enables you to increase your plant stocks quickly. The new plants will also be true to type, identical to the plant from which the cuttings were detached (they are clones). Be sure to use clean good stock when cutting from the original plant.
Underground stems (including bulbs, corms and tubers) can be divided and cuttings may be taken from roots as well, however, root cuttings may not be true to parental genotypes.
Budding and grafting is another form of asexual reproduction and some methods are explained in detail at the Hort. page.
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