Landscapers typically select drought-tolerant vegetation when designing rock gardens. But in regions where Bambi is an issue, your rock garden should also contain deer-tolerant plants. Below I discuss four perennials that should aid you in your control measures. These stalwarts handle both drought and Bambi pretty well, and they can be grown most anywhere in the continental U.S. (and across corresponding temperate zones). If you're not willing and/or able to install fencing, then at least growing what doesn't appeal to Bambi's taste buds may help keep these pests from eating up your rock garden vegetation.
When we speak of drought-tolerant vegetation for rock gardens, we're usually referring to two different characteristics at the same time. One characteristic is the ability to thrive in dry soils. The other is a preference for sunny conditions. Not that some members of the drought-tolerant tribe can't grow in shade; but more often than not they are sought for areas with lots of sun but little water.
Species native to your region will often thrive in rock gardens. Problem is, people often don't find them attractive enough to grow them in their rock gardens. The attractive perennials listed below can be purchased at nurseries.
Hens and chicks (Sempervivum tectorum) is a deer-tolerant or "deer-resistant" plant that forms attractive rosettes. Its succulent leaves mass together to form short, compact mounds. Hens and chicks does bloom, but the plant is grown for its foliage, not for this negligible, spikey flower. The tiny "chick" plants grow at the base of the "hen," or main plant. Detach the chicks and grow them elsewhere, if propagation is desired. Otherwise, just let them be, and they'll form a dense mat that essentially serves as a ground cover.
A similar group of deer-tolerant plants are the stonecrops (Sedum), for instance, Angelina sedum and Autumn Joy sedum. Stonecrop plants are a perennial favorite in rock gardens, as the "stone" in the name would suggest. Stonecrop's foliage consists of succulent leaves in whorls. The leaves are sometimes variegated and can range in color from bluish-green or greenish-yellow to reddish-pink or almost off-white.
Unlike hens and chicks, stonecrop produces a flower well worth growing in its own right. Stonecrop's flowers can be yellow, orange, red, or pink, in addition to the white pictured above. Flowers usually bloom in clusters above the foliage.
Barbed-wire fences may be effective in controlling Bambi, if they are tall enough. But why not put the barbed-wire right on the plant you need to protect? Well, that's just what prickly pear cactus does. Prickly pear cactus (Opuntia compressa) grows to be about 6"-14" tall, and it bears showy yellow flowers, 2"-3" in diameter. A prickly pear cactus in bloom positioned next to a red hen and chicks plant makes for a striking rock garden tandem. This is the only cactus found widely in the eastern U.S.
But your choices for deer-tolerant plants in rock gardens aren't restricted to cacti and succulents. Lamb's ears (Stachys byzantina) provides wonderful texture in rock gardens and spreads readily. Lamb's ear plants produce light purple flowers on tall spikes. Their silvery foliage has a velvety texture, which is how lamb's ears got its name. Apparently this same texture is unpalatable to Bambi and makes lamb's ears a deer-tolerant plant.
Grow these attractive, drought-tolerant, deer-tolerant plants in a well-drained soil with full sun, and you should have a perennial rock garden envied by all your neighbors -- except Bambi.