Spreading slowly but surely from underground runners, these low-growing evergreen perennials are invaluable ground covers for shady places. They are hardy to cold and well able to compete with tree roots. Compact growth and clean, attractive foliage are their chief virtues. Small spring flowers aren't showy when viewed casually, but they're attractive at close range.
For best growth, give well-drained soil amended with plenty of organic matter. Set 6 in. apart for reasonably quick cover; apply a mulch, and keep soil moist until plants are established. Give them light to full shade; too much sun causes foliage to turn yellow. Deer don't usually bother pachysandra.
P. procumbens. ALLEGHENY PACHYSANDRA, ALLEGHENY SPURGE. Zones US, MS, LS, CS; USDA 6-9. From the southeastern U.S. Not as widely available or as quick to spread as P. terminalis. Grows 612 in. high, with grayish green leaves (24 in. long, 23 in. wide) clustered near stem tips; leaves are often mottled with gray or brown. Fragrant white or pinkish flowers. Prefers neutral soil.
P. terminalis. JAPANESE PACHYSANDRA, JAPANESE SPURGE. Zones US, MS, LS; USDA 6-8. Native to Japan and northern China. Grows to 812 in. high. Shiny, leathery, dark green leaves, clustered at ends of stems, are 24 in. long and 12112 in. wide; upper half of leaf has shallowly toothed edges. White flowers are borne in 1- to 2-in. spikes. Popular selections include 'Green Carpet', shorter and denser in growth than the species, with shinier, deeper green leaves; 'Green Sheen', glossy leaves and more heat tolerant; 'Silver Edge' ('Variegata'), with creamy-edged foliage; and fast-spreading 'Cut Leaf', with deeply dissected leaves.
Japanese pachysandra can stand very heavy shade and is widely used under trees; it is also an excellent filler for those difficult spots where lawn grass won't grow. Luxuriant-looking, top-choice ground cover for shade in the Upper and Middle South. In the Lower South, it sulks during long, dry summers. Prefers slightly acid soil. Seldom bothered by pests, but a leaf blight can cause serious damage if it gets out of hand; control with fungicides and, if possible, by limiting overhead watering.