Most aeoniums are native to the Canary Islands. Their fleshy leaves are held in rosettes at branch tips. After several years, rosettes produce a single large flower stalk in spring or summer; branches that have flowered die. These cool-season growers go dormant in summer to save water. During dormancy, they may appear sick and lose leavesbut when the weather cools and the plants get water, they perk up and regrow leaves.
A. arboreum. Grows 3 ft. tall and wide. Each branch tip carries a 6- to 8-in.-wide rosette of bright green, fleshy leaves. The yellow flowers appear in long clusters. 'Atropurpureum', with magenta-and-green rosettes, is more striking and more widely grown than the species. Hybrid 'Zwartkop', sometimes called black rose, has very dark purple (nearly black) rosettes up to 10 in. across; it can reach 5 ft. tall.
A. 'Blushing Beauty'. Forms a full, tight mound of 8-in.-wide rosettes; the plant reaches 2 ft. tall and wide. Leaves are green with a pronounced red edge. Flowers are yellow.
A. 'Cyclops'. Resembles A. arboretum 'Zwartkop', but leaves are deep red rather than black, and each rosette has a green center, or eye. Plants grow 45 ft. tall and 34 ft. wide, with an open, branching habit.
A. decorum. Bushy, rounded, many-branched plant to 1 ft. high and at least as wide. Each branch ends in a 2-in. rosette. Fleshy, pale green, reddish-tinted leaves have red edges. A neat, compact grower with pink flowers.
A. haworthii. Free branching and shrubby, plants reach 2 ft. tall and 4 ft. wide. Rosettes of blue-green, red-edged leaves are 23 in. wide. Cream-colored flowers. Very tough, long-lasting plant that can take more cold than most.
A. 'Kiwi' (A. decorum 'Kiwi'). This popular, colorful plant forms a low, tight mound to about 112 2 ft. tall and 2 ft wide. Leaves are tricolored; light green with pale yellow variegation and bright red edges. Pale yellow flowers.
A. nobile. To 2 ft. tall and nearly as wide. An unbranched stem holds a rosette of thick, fleshy green leaves, often tinted reddish with maturity. After several years, rosettes produce a large (to 1 ft. high and wide), flat-topped cluster of red flowers on a thick, red stem. The plant dies after bloom but produces many seedlings.
A. 'Sunburst'. Showy plant with 12-in.-wide rosettes of green leaves variegated in light yellow or creamy white and edged with red. Usually grows 12 ft. high and wide but can mound up to 4 ft high. Flowers are cream colored. Does not respond well to pruning. 'Starburst' is similar, but with less yellow in the leaves.
A. tabuliforme. Unusual species with unbranched stems holds single, nearly flat rosettes just 26 in. high and 1018 in. across; sometimes called 'Dinner Plate'. Light green, hairy-edged leaves radiate from the center in perfect symmetry. After several years, a single 1- to 2-ft.-tall stalk of yellow flowers rises from the center. Plants die after flowering.
A. undulatum. Bright, apple-green leaves are wavy, forming unusual-looking rosettes 1015 in. wide. Stalks are thick and up to 34 ft. tall; makes offsets freely. Yellow flowers.
A. urbicum. Some say this is an A. undulatum hybrid. Dinner plate rosettes reach 815 in. wide. Long, narrow, gray-green leaves loosely arranged, have reddish edges. Forms stems several feet tall, unbranched except for offsets at the base. Does not respond well to pruning. White or pinkish flowers.