In temperate-Mediterranean climates, where annual rainfall reaches about 450mm, (18in) lawns need at least 700mm of additional irrigation through the hot, dry summer. That is, 700 liters per square meter per year. In drier climates, where annual precipitation does not exceed 250mm, (10in) this figure can rise to over 1,000mm a year.

Many ground cover plants on the other hand, can survive, grow, and prosper on up to 200mm of extra water, and some, when established, and providing that the rainfall for the year has reached 250mm, do not require any watering at all. While ground covers cannot replace the functional role of grass, such as playing and sitting, they can definitely be considered where there is no real need for a lawn. Ground covers for instance, are a far better option than grass for the narrow space at the side of the house, especially in shady spaces facing east, northeast.

Beautiful, low-growing plants with delicate leaves create a fine, frothy, textural quality, which is far more interesting than a flat, two-dimensional lawn. Subtle variations are achieved by the different shades of green available. Think of the dark, heavy green of Rosemary and Trachelospermum, combining with the fresh, light green of Baccharis pilularis, or Asparagus densiflorus “Sprengerii”. Low-growing species of Grevillea, with their fine foliage and striking red blooms, can takeover from a swathe of the very prostrate Myoporum parvifolium.

It is also possible to dot a few taller, narrow plants amongst the groundcovers, in order to create a vertical emphasis, accent, or “exclamation point”. Nandina domestica, (Heavenly Bamboo) with its attractive form and delicate foliage, fits the bill perfectly. It is also modest in its water requirements. Alternatively, grass-like ornamentals like Phormium tenax serve the same purpose.

Flowering ground covers, or ground cover plants that need full sun, fall into a separate category. It is important with these, not to shade them out by planting larger plants too close by. Many prostrate succulents, or ice plants, can be very exciting with their seasonal blooms, but they do require considerable care and attention to ensure they look presentable through the year. A sea of Lampranthus in flower for instance, is a sight virtually unmatched in gardening, yet the plant invariably looks untidy and leggy if neglected.

Ground cover plants are not a “substitute” for grass. Children cannot play on them and you can’t have a family picnic on them. Neither do they provide that neat, open view that we know and love with a lush green lawn. Ground covers have an aesthetic and design value of their own, which combined with the possibility of saving oceans of water, makes them so essential to the gardener in a dry climate.