Sometimes friends or neighbors offer to share starts, cuttings, or divisions of ground covers from their own plantings. Be sure that these are healthy and not too invasive before accepting the offer. Consider first the advantages of buying plants from local nurseries. Ask the nursery staffers questions—they are familiar with the area and the plants. Look at and compare the wide spectrum of available plant choices. Find plants with good color, vigorous growth, and a dense, compact shape rather than long, leggy stems.
Inspect the undersides of the leaves and their junction with the stem to be sure that there is no disease or insect infestation. Ask a salesperson to knock a sample plant out of the pot and show you the root system. There should be plenty of roots visible, but not so many that they are matted almost to the exclusion of soil. (Should you buy plants with matted or circling roots, break or cut apart some of the outside roots before planting.)
Plants can also be acquired through the mail. Purchasing from on-line or mail-order catalogs offers two major advantages—a vastly expanded choice of kinds and cultivars, and detailed information about the plant’s growth, habits, and ultimate size and shape—information that can be referred to after planting. Most nurseries carry only the most popular and familiar plants. Catalogs offer dozens or even hundreds more.
Ordering by mail has some drawbacks. Mail-order plants are usually smaller—for easier, less costly shipping. Their arrival date may not coincide with planting plans, and the condition of the plants before and after arrival is always a gamble. Therefore, the reputation of the nursery, the guarantee the nursery offers, and immediate care upon arrival are all very important. Unwrap the plants and check them for water at once. Expose them to light but not to hot sun or wind.
Whether buying plants at a local nursery or by mail, where there is a choice of available sizes and forms, remember that smaller plants are usually less expensive and take less time to recover from moving and transplanting. Larger plants, on the other hand, may save a season or more in reaching maturity or filling in an area.
Choosing a Plant
Ground cover plants are often sold in flats or containers. In general, for most ground covers, container-grown plants are better than bare-root plants. Plants are also available balled and burlapped. In some cases, gardeners will start their plants from seed. When buying other than a container-grown plant, the following guidelines apply.
Balled-and-burlapped plants Shrub-like, woody ground covers, such as spirea (Spiraea), cinquefoil (Potentilla), and forsythia, are often sold as balled-and-burlapped specimens. Balled-and-burlapped plants should have a solid earth ball firmly covered with the burlap. When planting, do not remove the burlap; simply loosen it once the plant is in the hole and then leave it to rot away, taking care that none is exposed above the soil level. If a plastic material is used instead of burlap to wrap the rootball, or a plastic twine to tie it, remove it before planting: Plastic or other synthetic materials will not break down in the soil.
Bare-root plants Bare-root ground covers are available during the dormant season. Many ground cover plants are sold bare root, dwarf periwinkle (Vinca minor) and big blue lilyturf (Liriope muscari) being among the most common. Bare-root plants require immediate planting and careful tending for the first several days to two weeks but are often much less expensive to buy and ship.
Plants sold by the flat or cell There is usually a price advantage to buying an entire wooden or plastic tray full of ground cover plants. Many are sold this way—spurge (Pachysandra) and wintercreeper (Euonymus) are good examples. Plants in flats or cells are smaller than those available in individual containers and take less labor, space, and soil mix to assemble.
Check the number of plants in the pack. There should be a minimum number of empty spaces. Check for plant vigor and health. Plants from flats with separate sections will transplant with less shock. In an open, unsectioned flat, it may be less disturbing to cut squares of soil and roots for each plant rather than to pull apart the root sections. For the best results, cut the flat into blocks containing individual plants a week before you plant. This gives the roots a chance to regenerate within the block.