Plants which do not exceed 45cm (18in) in height are often referred to as "ground cover", particularly when they have a spreading habit and can be used as a means of softening and disguising hard edges or straight lines.
Low-maintenance Solutions
Low-growing and ground-covering plants are useful for the city front garden in a number of ways, both in the garden and around its edges. They are ideal for softening the edges of a path when they are allowed to grow partly on to the hard surface, and they can be dotted in planting holes left among the slabs, to break up a large expanse of paving. If you have borders in the front garden, ground-cover plants fill and soften the front of the border and will soon fill all gaps. This, in turn, helps to suppress weeds, because, in common with most other seedlings, weeds need light to grow. Eliminating the need to cultivate the soil to get rid of weeds will also help prevent more weeds from appearing, as no more seeds are brought to the surface. Thus ground cover is ideal for the city garden, as it is low-maintenance.
Another bonus is that a covering of leaves over the surface of the soil reduces the amount of water lost to evaporation on a warm or windy day. The soil is kept moist and the amount of water needed to keep the other plants alive is reduced.
Many of the plants used as ground cover are quite tough, and require little in the way of maintenance after planting. Hypericum calycinum, for instance, simply needs annual clipping with a strimmer (string-line trimmer), to reduce the height and encourage bushiness. Other than that, an annual feed will suffice for it to thrive.
Thus, when the amount of time available for maintenance is limited, as it often is for city gardens, using a low covering of plants can reduce the necessary work quite considerably, while still providing a welcoming entrance to your home.
Planting Ground Cover
1. To plant ground cover; clear the ground of weeds first. Annual weeds can be hoed off or killed with a herbicide. Some perennial weeds will have to be dug out by hand.
2. Fork in as much rotted manure or garden compost as you can spare, then apply a slow-release or controlled-release fertilizer and rake it in lightly.
3. Unless your ground cover spreads by underground stems it is best to plant through a mulching sheet to control weeds while the plants are becoming established. Cut a cross where the plant is to be positioned.
4. Plant in staggered rows, planting small plants through the slits with a trowel. Water thoroughly after planting and in dry weather throughout the first year
5. Until the plants have grown together you may want to use a decorative mulch such as chipped bark to improve the appearance.
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