Your nose lets you know once you’re approaching a planting of cistus or rock rose (Cistus spp.) , the most commonly grown stone rose. The leaves and stalks of those tiny shrubs have a characteristic resinous smell. The white, pink or red blooms have wrinkled, crepe-paper textured petals. Closely related rockroses from the Halimium genus appear similar. Both these Mediterranean rock roses can be lightly pruned but shouldn’t be cut down. Texas stone rose (Pavonia lasiopetala) responds well to more severe cutting back.
Cistus Rock Roses
Drought-tolerant and equipped to reside in poor, rocky soil, cistus require little maintenance. The shrubs have green to gray-green leaves. They flower in spring and early summer with abundant blooms, though each flower lasts just 1 day. The branches are slender but woody. Cistus does not take well to pruning, except for a light pinching back in late fall or winter, and even this can negatively impact blooming. Horticulturist Andy McIndoe, in his novel “The Horticulture Gardener’s Guides — Shrubs” advises not to prune back to tough wood to get cistus. Cistus are generally short-lived shrubs, lasting about eight to a decade. They grow in U.S. Department of Agriculture plant hardiness zones 8 through 10, depending on the species and cultivar.
Halimium Rock Roses
Nearly all Halimium stone roses have yellow flowers, often with a reddish-brown blotch at the foundations of petals. The trees have green to silver leaves and bloom profusely in spring. Many have a mounding shape with blooms held on stalks above the foliage. Some of those rock roses benefit from light pruning when they flower to get rid of old flower stalks and spent leaf, but generally do not require cutting or cutting being cut down. Some species have reddish to brownish tiny fruits following flowering, and people may be left on the plant until the shade is gone. After that, cut the old fruiting stalks. These stone roses grow in USDA zones 7b through 10b, depending on species.
Halimiocistus Hybrid Rock Roses
Drought-tolerant hybrid stone roses usually have mounded growth and showy, abundant yellow or white blooms from spring to summer. These hybrids typically don’t require regular pruning and ought never to be cut down severely. Most grow in USDA zones 7a through 9b. The trees can be gently shaped by hint pruning in late winter.
Texas Rock Rose
Texas stone rose has showy, dark pink flowers and velvety, heart-shaped green leaves. It gains from tough cutting back in early spring since new growth is frequently leggy. To encourage bushiness and more blooms, prune the stems back occasionally throughout the growing season. The plants live for three to six decades, but they self-seed in if not deadheaded. Growing in USDA zones 8 through 9, Texas stone rose does best in full sunlight and is drought-tolerant once started. For any rock rose trimming, disinfect the tools by wiping them with a cloth soaked in rubbing alcohol, before and after use and between plants.