If you're looking for a tough, easy-to-grow groundcover for a shady spot, pachysandra (Pachysandra spp.) could be the perfect choice. Also called spurge, two species are commonly cultivated: Allegheny spurge (Pachysandra procumbens) and Japanese spurge (Pachysandra terminalis). Both plants grow in U.S. Department of Agriculture plant hardiness zones 5 through 9 and are usually trouble-free, spreading quickly to fill in open areas.
Preparing the Area
Plant pachysandra in the garden any time in spring or early summer, when the plants can get off to a good start before cold weather arrives. Both types of spurge do best when given partial to full shade for most of the day; a spot under tall trees that gets shifting shade is ideal. Once established, the plants can tolerate some sun, but too much sun may cause leaves to bleach, changing from a rich green to a paler, yellowish shade.
Once you've chosen the location, it's helpful to turn the soil to a depth of about 6 inches with a spade or fork, loosening it so new roots can grow freely. This plant prefers organically rich soil, so spread about 2 inches of compost on the soil's surface and turn it into the soil while you work. Compost boosts the soil's fertility and also improves its ability to hold moisture, a plus for this plant.
Setting Out Plants
For plants ready to grow and fill in an empty area, start with young spurge plants, available from most garden centers and nurseries. Both spurge varieties grow to a width of about 1 foot, so space new plants about 6 to 12 inches apart. Tap the side of the nursery pot to loosen the root ball, then gently turn the plant out of its pot. Using a trowel, dig a hole for each plant about twice the size of its root ball. Set the plant at the same depth as it was in its nursery container and backfill the hole with soil, tamping it down well. Water the new plants thoroughly, flooding each to ensure no air is trapped around its roots.
Providing Adequate Moisture
Spurge plants are quite tolerant of some dryness once established, but it helps to keep the soil evenly moist during the first season or two, to get the plants off to a good start. Water whenever the top inch of soil feels dry to your fingertip, but use a soaker hose or drip irrigation to keep foliage dry and prevent growth of fungus.
Spreading about 1 inch of finely shredded organic mulch under each plant also helps conserve soil moisture and keeps down competing weeds. Place the mulch under each plant but keep it back a bit from the plant's center to prevent fungal problems.
Other Early Care
Spurge plants don't require regular fertilization, growing well and spreading quickly in average garden soil by sending out underground stems called rhizomes that develop into new plants. Over time, a planting enlarges to completely fill in the area with dense foliage.