Low-clumping or slow-spreading plants are the best type of plants for rocky areas. Perennials or small shrubs are better than annuals, because annuals have to be replanted each year.
Plants that grow well in rocky landscapes need little water and require excellent drainage. The plants should be set in pockets between the rocks that have been filled with humus-rich soil. Clay soil should be amended with organic matter to improve the texture and drainage.
Ice plant (Delosperma sp.) grows 2 to 6 inches tall in full sun. Pink, purple, salmon or yellow flowers bloom in summer.
Numerous varieties of sedums grow in full sun. They vary from 1 to 15 inches in height. Some sedums are evergreen.
Bugleweed (Ajuga reptans) grows 2 to 10 inches tall in partial shade to full shade. It blooms in late spring to early summer with purple flowers. The foliage may be green, bronze, chocolate brown or pinkish, depending on the variety.
Creeping phlox (Phlox sublata) forms a dense 4-to-6-inch-tall mat. The white, pink or lavender flowers cover the foliage in the spring. It grows best in full sun.
Verbenas grow 3 to 6 inches tall with trailing stems. White, pink, purple or red flowers appear in summer. Verbenas grow best in full sun.
Dianthus grows 6 to 12 inches tall in full sun. The flowers are shades of pink, rose, crimson and white. The foliage is grasslike in shades of dark green, gray-green or blue-green, depending on the variety.
Heucheras grow 8 to 18 inches tall in sun or partial shade. Most have variegated foliage in shades of green, gray, silver, gold, chartreuse, peach, orange or red.
Nana coreopsis (Coreopsis auriculata ‘Nana’) forms a dense mound 4 to 8 inches tall and wide. The orangey-yellow flowers bloom from summer to fall. It grows best in full sun.
Lavenders grow in full sun. The purple or violet flowers appear in late summer and early fall. The plants grow 5 to 18 inches tall.
Thyme (Thymus sp.) grows up to 12 inches tall in full sun. It may have a spreading or upright form, with pink or purple flowers in the summer. The foliage smells like lemons, oranges or other spicy scents, depending on the variety.