Growing your own plants from seed or increasing your stocks from existing plants can be one of the most satisfying aspects of gardening; not only is it an economical way of filling the garden, but it is also an opportunity to rear plants that are not widely available and allows the gardener to produce back-up stocks of plants that are liable to die in cold winters or generally short-lived.
Propagation is the name given to the various ways of initiating plant growth or multiplying those already in existence. The most useful forms of propagation for the amateur gardener are sowing seeds, taking cuttings, grafting, layering and dividing plants.
These are vital techniques to learn if a gardener wishes to progress in skill. As well as being useful, it's fairly easy to practise, you can use plants from your garden, a plant nursery or even, say, M&S Flowers and in no time you'll be surrounded by newly propagated cuttings.
Growing from seed is the best method for raising vegetables, hardy and half-hardy annuals and biennial flowers, and is also a good way of growing many hardy perennials. Although it can be suitable for propagating shrub and tree species, it is slower than other means. Hybrids or cultivated varieties ('cultivars') should be propagated asexually by taking cuttings, layering or division (known as vegetative propagation), as they cannot be depended upon to come 'true' from seed. Division is an easy way of replicating hardy perennials and many alpines, and has the bonus of rejuvenating existing clumps.
Cuttings may be taken from plants that would take too long to grow from seed, or from hardy and half-hardy perennials to increase stock. Layering is, in essence, a form of taking cuttings; the difference is that shoots of a plant are encouraged to make roots before being severed from the mother plant. This technique is helpful for clematis, and for shrubs which grow branches close to the ground.