STARTING NEW PLANTS FROM PARTS

Seeds and transplants are not the only forms from which to raise new plants; they're the forms you'll use most often, but some vegetables are started from other plant parts — suckers, tubers, slips, crowns, sets, cloves, divisions, or cuttings. In some cases plants can be grown either from seed or from plant parts. Onions, for instance, take a very long time to germinate from seed, so it usually makes more sense to grow them from sets. Other plants grow best from plant parts. The following are ways to start vegetables from plant parts:
Suckers. Suckers, or offshoots, are plants that grow or shoot up from the root system of a mature plant. These suckers are dug up and divided from the mother plant, then transplanted to mature into new plants. Globe artichokes are usually the only vegetables grown from suckers.
Divisions. Divisions, like suckers, occur naturally in the form of small rooted plants or bulbs that grow from the mother plant, and get their name from the way you separate — or divide — them off to grow as individual plants. You can dig up the new growth as it appears and replant It. Or, as with bulbs, you can dig up the mother plant, separate the small new bulbs, and replant each unit. Horseradish and rhubarb are grown from divisions. You can divide plants in spring or in fall; fall is preferable, because the cool, moist weather gives the new plants better conditions in which to become established.
Cuttings. Cuttings are divisions that don't occur naturally. You obtain them by cutting a piece of stem or side-branch from the plant at a node — a lumpy area on the stem. The cutting is then placed in the soil and forms its own roots. You can also put the cutting in water until roots form.
Slips. Slips are young, tender, rooted cuttings or sprouts grown from roots. Sweet potatoes are the only vegetables commonly grown from slips.
Tubers. These are specialized swollen underground stems, capable of producing roots, stems, and leaves. Irish potatoes and Jerusalem artichokes are usually grown from tubers. When the tubers are cut up for planting, as in the case of Irish potatoes, they are called seed pieces.
Crowns. These are compressed stems near the soil surface that are capable of producing leaves and roots. Crowns are often planted with the roots attached, in which case they're more accurately referred to as roots. Crowns can be divided when the plants are dormant. Asparagus is usually grown from crowns.
Sets. Sets are one-year-old onion seedlings that were pulled when the bulbs were young. The bulbs are then air dried, stored for the winter, and planted the next spring. Onions are the only vegetables grown from sets.
Cloves. These are the segmented parts of a bulb; they're also called bulblets. Garlic is the only vegetable commonly grown from cloves. Each garlic bulb is made up of a dozen or more cloves, and you plant each clove separately. Don't divide the bulb until you're ready to plant; separating the cloves too early may result in lower yields.