The Connective Tissue of Landscape Compositions
Ground Covers and facer plants complete the edge of a triple-level vegetative screen. They hide unsightly, leggy shrubs and define shrub bed borders. A ground cover is a mass of low plant material that acts to unify the ground plane and protect the bare soil, but it isn’t mowed or cultivated like turf. Turf provides a walking surface. A ground cover, in contrast, actually acts to discourage foot traffic and protect tender surface roots of nearby shrubs and trees. Ground covers provide the finishing edge and unifying connection to the soil for a shrub bed.
Choosing ground cover species for a landscape setting is a complex task. It is important to know which ground covers grow in a uniform, dense mat, and which prefer spotty growth or small groups. The natural vegetation floor isn’t amenable to vast sweeps of uniform plant material. The unaffected ground plane is a wild mix of multi-layered and diverse plants with a succession of growth and bloom and change. Native ground covers and grasses prefer to grow in clumps rather than sweeps, and they welcome competition from neighboring volunteers. The best choice is a tapestry of different low shrubs to fill in the ground plane as a living mulch and provide a definitive edge for plant beds.
Establishing a new ground cover bed often starts with the initial step of killing everything that is growing in the plot and covering the remaining soil with a layer of mulch to prevent new seedlings from trying to return. Avoid tilling near existing shrub and tree roots. Space new plants so they fill in thickly. Many ground covers can be propagated by division, which is great. You can establish new beds with inexpensive divisions from existing plants.
A ground cover planting often acts as a propagation bed for competition from weeds. The natural inclination for ecosystems is to cover and fill every spot of bare ground, and if weeds can grow into place first, they will. The assumption that a ground cover bed can be a self-sustaining, no-maintenance area is overly optimistic. Natural equilibrium is the lazy gardener’s goal, but ground covers won’t stand for idleness. The cooler the climate, the longer the wait for a full-grown ground cover bed, but the less work to keep it weed-free. Once established, most ground cover plantings need to be hand- weeded with vigilance and persistence. Plant and then prepare for battle. Maintenance should focus on removing weeds quickly. Density of coverage determines how easy or difficult the weed patrol will be.
Space new plants so they fill in thickly and quickly. Small, herbaceous ground covers like Mondo Grass can be planted as closely as six inches apart in staggered rows. Herbaceous perennials and woody ground covers need to be one-and-a-half feet or less apart. Large coniferous woody ornamentals like Junipers can be spaced as much as two-and-a-half feet on center. Proper spacing is related to each type of plant, but keep plants as close as your budget and the species allow.
If ground covers are planted in areas with heavy leaf litter, you may need to carefully rake or blow fallen leaves away to prevent the energizing sun from being blocked. Take care when applying fertilizers to avoid chemical burn spots on the ground cover leaves. Good sanitation helps prevent weeds and disease problems. Remove spent foliage and flowers, rather than allowing debris to remain in a ground cover bed over winter.
Whatever the garden design, ground covers are an essential part of the landscape. Choose something to cover the ground, before the ground sprouts its own selection. There are a lot of good things to appreciate in ground covers. They provide textural and color variations. They often provide year-round color. They break up the soil where they grow. They can result in reduced maintenance if monitored often. Ground covers discourage foot traffic near tender roots of shrubs and trees and provide living, breathing mulch. If massed, they unify and soften the edges of plant beds. They hold the rest of the elements in a landscape composition together visually, creating a logical footprint for the horizontal plane. They are a creative way to keep the bare ground clothed, acting as the connective tissue of your landscape design.