Drought-Tolerant Ground Cover Underneath an Olive Tree

Fragrant Herbs

• Thyme (Thymus spp.) is a tiny-leaved ground cover that can be used along the edge of pathways or between stepping stones where they pass near an olive tree. Thyme can be grown in USDA zones 5 to 9 and comes in many fragrant forms – including lemon-scented thyme, elfin thyme and wooly thyme. Oregano (Origanum vulgare) forms a ground cover about 12 to 16 inches tall and comes in several ornamental cultivars, besides the standard culinary form. Try growing it beneath olives in USDA zones 4 through 9.

Evergreen Woody Ground Covers

• Ceanothus, or California wild lilac (Ceanothus spp.), is known as a drought-tolerant shrub, but the Point Reyes ceanothus (Ceanothus glorious) grows as a ground cover only 6 to 12 inches tall. The rounded, dark green leaves are a pleasing contrast beneath the grey-green foliage of olive trees. This variety of California lilac has fragrant powder blue flowers and is hardy in USDA zones 8 to 10. Like ceanothus, manzanita (Arctostaphylos spp.) is commonly known as a shrub, but also exists in a ground cover form called California bearberry (Arctostaphylos uva-ursi) . It has coppery brown bark with fine, dark green foliage and is hardy in USDA zones 7 to 10.

Grasses

• The soft tufts of pink muhly grass (Muhlenbergia capillaris) are a great compliment to olives with their pinkish seed heads that rise up to 3 feet. This species spreads slowly to colonize small areas but is not particularly invasive. Pink muhly grass is grown as a perennial in USDA zones 6 through 9, but can be grown as an annual in colder climates. New Zealand hair sedge (Carex comans) grows in neat clumps about 12 to 16 inches tall and wide. Growing in USDA zones 7 to 9, the grass is attractive year-round with minimal irrigation.

Shrubby Ground Covers

• Mahonia “Soft Caress” is a low, shrubby version of the popular shrub. As its name implies, the foliage is softer than its prickly cousins. The stems are about 2 feet tall with brilliant yellow flower stalks rising above the dark green foliage. This cultivar spreads slowly by rhizomes to form a colony and is good for a backdrop under olives in USDA zones 7b to 10. Cleveland sage (Salvia clevelandii) is a drought-tolerant grey-green shrub that erupts with light blue flowers in late winter and spring. It grows about 3 feet tall and slightly wider and makes a nice understory companion for olives in USDA zone 9 to 11.