Earlier descriptions explained that these special landscape plants do not have the large root balls common to trees and shrubs. They are seldom planted in individually prepared holes, but rather are set shallowly into prepared planting beds.
Bedding Plants and Groundcovers
The spacing of the plants will determine the time required to attain the effect desired. Predictably, closer spacing will result in more rapid coverage, but it will also increase the expense of both labor and mate-
figure 10-12. Alternating the placement of bedding plants and groundcovers fills space most efficiently. (Delmar/Cengage Learning)
rials. Table 9-4 in Chapter 9 lists some of the most common species of groundcovers, their optimum spacing, and selected other characteristics. To ensure even and maximum coverage, bedding plants and groundcovers should be installed in a staggered planting pattern (Figure 10-12).
Frequent waterings are needed to prevent the transplants from drying out and to encourage deep rooting. Mulching, surprisingly, is not always recommended. Coarse mulches can discourage the lateral spread of the small plants and delay or entirely prevent their filling the bed area. Generally, mulching is not recommended for bedding plants. It can be helpful with groundcovers to prevent their heaving to the surface following the alternate freezing and thawing of winter soils. If used, the mulch for groundcovers should be fine textured and applied after the ground has frozen, not at the time of installation.
Flowering bulbs require a rich, well-drained soil. They are planted either in flower beds and borders or as masses in the lawn. They may be gently tossed by the handful into open, turfed lawn areas to be planted wherever they land, in an irregular spaced pattern. Bulbs are planted at differing depths and spacings depending on their species. Table 10-2 lists the depths and spacings of some common bulbs.
Bulbs are always set into the ground with the base oriented downward and the shoot pointed upward (Figure 10-13). Many can be installed with a bulb planter.
Other bulb-like structures, called tubers and rhizomes, are installed in mounded holes that permit the structure to be oriented horizontally and the roots directed downward (Figure 10-14). As always, the backfilling step should be done carefully to ensure that no air pockets form. Water collecting around the bulbs in air pockets can promote rotting.
figure 10-13. Bulbs are installed either by hand or with a bulb planter. They are set into the ground "noses up" and are covered with soil pressed firmly to prevent air pockets. (Delmar/Cengage Learning)
figure 10-14. This iris rhizome is installed by spreading its roots evenly over a mound of soil, then backfilling to cover the roots while allowing the leaves and top of the rhizome to remain exposed. (Delmar/Cengage Learning)