The familiar sandalwood, Myoporum laetum, that is such a resilient small tree or big shrub in windy coastal climates, might make the wrong impression for the less familiar creeping myoporum, Myoporum parvifolium. Creeping myporum does not get much more than a foot high unless it climbs over stones or other obstacles, and it might stay less than six inches deep in exposed spots.
The evergreen foliage is dense enough to prevent most weeds from getting through. The tiny and narrow leaves are only about half an inch or an inch long, perhaps a bit longer. Clustered white starry flowers that begin to bloom late in spring continue to bloom through summer. Although tiny, and neither profuse nor remarkably showy, they are a nice accent to the rich green of the foliage.
Creeping myporum prefers full sun and occasional watering. It rots easily if watered too much. Its other weakness is that it does not tolerate traffic well. Creeping myoporum is a low growing shrub with woody stems that can break if trampled on. Individual plants can get ten feet wide if they get the chance. They are typically planted much closer together so that they cover the ground faster.
Lawns composed of turf grasses are the most functional, but also the most demanding forms of groundcover. That is old news. There are so many other less demanding low growing plants that that can cover the ground in areas that are not used like lawns are. Sometimes they work nicely just to control weeds. Sometimes they help to control erosion on otherwise unlandscaped hillsides.
Like all other plants in the garden, groundcover plants must be appealing. There is no point in growing plants that look no better than the bare soil they are intended to obscure, or the weeds they are intended to control. Some provide good foliage. Some bloom nicely. Many do both. Although not as resilient to wear as turf grasses, some groundcover plants tolerate some degree of traffic.
There are of course all sorts of groundcover. Only a few want as much water as lawns need. Some need no watering at all once established. Some are low growing shrubbery like sprawling forms of ceanothus, coyote brush, cotoneaster, coprosma and juniper. Others are vines like honeysuckle and ivy. Some of the best are creeping low perennials like iceplant, gazania and African daisy.
Low growing shrubberies may not be practical for confined spaces. When they run out of room to grow laterally, they tend to pile up on themselves, and some types can eventually get quite deep. Some types look silly if pruned around the edges for containment. Vines however need to be pruned around the edges, as well as out of trees and shrubbery. Some vines eventually get deep too.
Sprawling perennial groundcovers are the lowest and tidiest of groundcovers. They might not be as practical as shrubbery or vines for large areas, but are more often the better options for tight spaces. They do not mind getting pruned around the edges, and generally do not need any other pruning, although some look better if mown annually. Periwinkle and Saint John’s wort can get deep enough to get sloppy. Many other perennial groundcovers stay low enough to barely get disheveled by light trampling.