Many attractive perennial ground covers flourish in rocky, sandy or gravelly sites that provide little in the way of nutrients. Most are drought-tolerant plants that have extensive root systems that penetrate deeply into the ground, holding the plant firmly in place while tapping into any underlying sources of moisture. By choosing ground covers that are well-adapted to poor soil situations, gardeners in less-than-ideal climates can create show-stopping displays of flowers and foliage, effectively filling otherwise empty sites.
Sun-filled spaces are ideal for a low-growing plants such as sedum, creeping juniper, western mugwort and bearberry. Unobtrusive, yet eye-catching, these plants make excellent ground covers for harsh gardening conditions since they originate from some of the most severe climates on the continent. Consequently, they are able to tolerate dry weather, full sun exposure, salt spray, high wind, poor soil and acid to alkaline conditions. These perennials are ideal for covering steep hills or hot, dry sites and are exceptional for stabilising slopes or sandy embankments.
The combination of nutrient-poor soil and shade creates a gardening site that is difficult to fill, since most plants need both fertile soil and light to flourish. However, hardy plants such as bishops weed, yellow corydalis and woolly thyme thrive in conditions that daunt other perennials. These rapidly-spreading, ground-hugging plants cover the garden with carpets of fine-textured foliage and small, seasonal flowers, effectively filling the shadowy spaces beneath trees, shrubs or large landscape features.
Though traditionally trained to scale trellises, fences and posts, robust perennial vines, such as five-leaf akebia, trumpet vine, and cup-and-saucer vine can also be used as ground covers. Without a vertical object to climb, these resilient vines will scramble across the ground, covering the yard in a loose layer of flowers and foliage; however, even when planted in poor soil, these vigorous plants can grow out of control, threatening nearby flora and working their way into areas of the yard where they are not welcome. Vines must be pruned regularly to keep unwanted growth under control.
Working With Poor Soil
Poor soils tend to be dry and, as a result, gardens may require frequent irrigation, even when the appropriate plants are selected. Soil conditions can be improved by incorporating large quantities of organic material into the garden prior to planting. Simply spread a 6-inch layer of mature compost or well-rotted manure over the intended planting site, then use a shovel to mix the material into the top few inches of garden soil. After the plants have been installed, cover the garden area with a 4-inch layer of organic mulch. This not only helps prevent the growth of competitive weeds, it slows the rate of evaporation; consequently, gardens require less watering. Additionally, organic mulches will decompose over time, enriching the surrounding soil and providing nearby plants with an ongoing source of vital nutrients.