Succulents have a waxy coating on the leaves that prevents water loss and shields them from the heat of the sun. Many are native to desert regions, but the five listed below will thrive in most places, holding up to almost anything Mother Nature can throw at them. Plus, these five succulents offer a stunning palette of color and texture through the seasons. Try combining them in a rock garden, or in any sunny (but well-drained!) location that is too hot and dry for more dainty plants.
This is by far the largest and most diverse group of succulents that gardeners have to choose from. Most grow as a tiny groundcover less than 6" tall, and are known more for their colorful leaves than their flowers, but the variety 'Autumn Joy' sticks out above the rest rising 24" tall with broad crimson-bronze flowers that last late into fall. Popular low-growing varieties include 'Dragon's Blood' (reddish purple leaves) and 'Blue Spruce' (blue-gray leaves). Cold hardiness varies, but most survive down to USDA zone 3.
Echeverias are generally quite petite, growing no more than a few inches tall, and have a 'rosette' form—a circular arrangement of leaves that emerge from a stem low to the ground. But that is where the commonalities among the dozens of named varieties ends—'Afterglow' has spade-shaped leaves with a pinkish tinge; 'Black Prince' has pointy, chocolate-colored leaves; 'Albicans' has rounded silver-white leaf lobes; 'Blue Curls' has wavy-edged leaves that are silvery blue toward the center and pinkish red on the perimeter. Most are hardy to USDA zones 8 or 9, but where they aren't hardy they will thrive in a pot and can be brought indoors for winter.
This is the other goof-proof succulent that grows in low-lying rosettes, which comes in just as many colors and leaf forms as echeverias. Also known as houseleeks or hen-and-chicks, each individual sempervivum clump self-propagates by sending out little baby versions of itself attached to short stems (the 'hen' and its 'chicks'), spreading into a dense groundcover mat in the process. Cold hardiness varies, but most survive down to USDA zone 4.
Not all succulents are so tiny. Agaves are like monstrous cousins of sempervivums and echeverias—they have the same rosette form and wildly variable leaf colors, but grow from 2-6' in diameter—creating an otherworldly vibe in the rock garden. Some have thorny edges, such as Agave americana, but there are soft and smooth-edged varieties to choose from as well, such as Agave gemniflora and Agave victoriae-reginae. Cold hardiness varies considerably, but many varieties are hardy as low as USDA zone 5.
Aloes are about as tough and low maintenance as a plant can get—just toss a piece of leaf out in the yard and is likely to sprout where it lands. They range in size from sempervivums to agaves and beyond; some even grow into small succulent trees. Like agaves, they have strap-like leaves, which are known more for having unusual mottled patterns on their surface, rather than color variations. Aloes are also known for their striking flower displays, unlike most succulents. For example, one of the most commonly available varieties, Aloe brevifolia, has bright orange flower spikes in winter. Most aloes are not hardy below USDA zone 8, though the smaller varieties can be grown in a pot and brought indoors for winter.