If your only exposure to Rockroses has been the Orchid Rockrose (Cistus purpurea), which can get a bit rangy and raggedy after a few years, you are in for a real treat!
There are some spectacular varieties of Rockrose on the market, and these plants easily fill that challenging niche of a drought-tolerant, deer resistant, evergreen shrub with showy blooms. They do require well-drained soil - not too fertile is best - and minimal summer water once established.
Cistus are native to the Mediterraneas region and thrive in our hot, dry summers and mild, wet winters. They do especially well on a slope or rocky hillside with well-drained soil. Make sure they are placed in a location that gets winter sun. Rockroses look great as a mass groundcover (they usually are wider than tall) or mixed in a drought tolerant bed of lavenders, rosemaries, Ceanothus and other Meditteranean plants. Each individual flower doesn't last long but they bloom successively over many weeks. They don't tolerate heavy pruning, just annual tip pruning to keep them compact.
Here are some of our favorites:
Cistus skanbergii - A beautiful little groundcover Cistus. And abundance of soft pink 1" wide flowers are complemented by gray-green leaves. Low, broad habit- 3' tall and up to 8' wide.
Cistus 'Blanche'- a large shrub in habit and bloom. Ours have grown well over 5' tall and about 4' wide in 4 years. Seems to be more upright than wide with an especially resinous and scented medium green leaf. Needs some tip pinching to keep dense but has a nice habit for a large hedge. Extra large white blooms with yellow center. Seems to be one of the most deer resistant because of its resinous leaves.
Cistus ladanifer maculatus- Crimson Spot Rockrose - shown above. White petals with crimson spot at base. Rounded habit to at least 4'x4' and dark green leaf.
Cistus 'Sunset'- Another good rockrose for groundcover. 'Sunset' will spread at least 4-5' wide and stay 18"-2' tall, with bright magenta flowers on sage green/silver foliage. Great contrast and long blooming.