Ground covers are arguably the hardest working plants in the garden, holding strong against weed invasions, and protecting soil from erosion and desiccation. This is certainly true in Hawaii, where a year-round growing season gives weeds a distinct advantage. Well chosen ground covers can give your garden a neat, polished appearance, and significantly reduce maintenance. Selecting the right ground cover is largely a matter of matching the plant’s cultural requirements with the conditions of your location.
Plants for Sunny, Dry Places
Akia (Wikstroemia uva ursi) is a shrubby, Hawaiian native plant, which grows from one to three feet high. It produces attractive, blue green foliage, and has a compact, spreading habit. Akia is nearly always covered with small, yellow flowers and bright red berries, which add to its considerable charm. This plant is quite wind, drought and salt tolerant, and will do well in almost any well drained soil.
Ilima papa (Sida fallax) is a nearly prostrate, creeping native, which grows to three inches high. It produces masses of pretty, cup shaped, golden flowers, which contrast nicely with its gray green foliage. Ilima papa must have full sun and excellent drainage, and because it is highly tolerant of drought, salt and wind, it is a perfect choice for coastal gardens.
Plants for Sunny, Moist Places
Bacopa (Bacopa monnieri), or water hyssop, is a low, creeping plant, native to Hawaii and other tropical coastal areas. It forms a thick carpet of small, succulent leaves and tiny white flowers, from one to three inches thick. Bacopa thrives on moist soils in full sun and can tolerate direct salt spray.
Golden glory (Arachis pintoi) is an excellent choice for rapid cover in sunny locations. It forms a dense mat of bright green leaves six inches high with yellow pea shaped flowers held slightly above the foliage. This deep rooted plant is a great choice for banks and slopes. It is an ideal ground cover for orchards because it fixes nitrogen and does not need to be mowed. Golden glory tolerates some drought, but has little salt tolerance and does poorly in coastal locations.
Plants for Shady Places
Kupukupu (Nephrolepis cordifolia) is a spreading native fern, with dense, upright sword shaped fronds. Many cultivars are available in heights ranging from eight inches to two feet. Kupukupu does best in light to medium shade, in moderately moist soils, but can tolerate higher light and some drought. Compact, low growing varieties are ideal for planting under trees in semi shade.
Red Ivy (Hemigraphis alternata) is a colorful ground cover native to Malaysia, which grows three inches high. In deep shade its upper leaves turn silvery, while the undersides are colored a deep purple red. In partial shade the leaves turn deeper shades of green and purple. Several cultivars are available, including the waffle plant (H. alternata “Exotica”) with crinkled foliage. Red ivy does best in moist, well drained soil in partial shade. It works well on slopes, but is not salt tolerant. This plant’s deep contrasting colors make it a dramatic addition to the garden.