Superb as accents, focal points, or in combination with plants of contrasting texture, agaves command attention with their large, fleshy, straplike leaves and tall, unearthly looking blossom spikes. Flowering is sporadic, however, and may not occur for years. The original plant dies after it blooms, leaving offshoots that make new plants.
Gardeners familiar with diverse succulents will note that the former Manfreda genus has been merged with Agave. These agaves look like crosses between century plant (Agave) and tuberose (Polianthes). Unlike other agaves, they do not die after blooming. Long, mostly spineless, succulent leaves grow in a rosette from a bulbous base. Flower spikes are tall and sturdy, requiring no staking. The blooms are conversation pieces, good for cut flowers, and appealing to hummingbirds.
The species described here are all easy to grow in well-drained soil. Good in rock gardens and containers.
Like all succulents, agaves tolerate drought but demand excellent drainage. They grow well in containers and are not browsed by deer. Most are tender, but some species withstand freezing weather. Wet soil in winter decreases hardiness. Good plants for coastal gardens.
A. americana. CENTURY PLANT. Zones LS, CS, TS; USDA 8-11. From Mexico. Blue-green leaves to 6 ft. long, with hooked spines along the edges and a wicked spine at the tip. The species is variable but usually makes many offsets. Be sure you really want one before planting it; its bulk (to 8 ft. tall and 12 ft. wide) and spines make it formidable to remove. After 10 years or more, a branched, 15- to 40-ft. flower stalk bearing yellowish green flowers appears. A. a. 'Mediopicta Alba' is about half the size of the species, with a cream stripe down the center of each blue-green leaf. The subspecies A. a. protoamericana is hardy in the Middle and Lower South.
A. attenuata. FOXTAIL AGAVE. Native to mountains of Jalisco, Mexico. Spineless, fleshy, and somewhat translucent leaves are soft green or gray-green and up to 212 ft. long. Clumps grow to 6-8 ft. across, and older plants develop a stout trunk to 5 ft. tall. Arching spikes to 12 ft. long are densely set with greenish yellow flowers. This species will take poor soil but does best in rich soil with regular water. Protect it from frost and hot sun. It makes a statuesque container plant.
A. 'Blue Flame'. Zones CS, TS; USDA 9-11. An elegant, clump-forming hybrid with rosettes of spine-tipped, blue-green leaves to 2 ft. high and 2 ft. wide. Looks like parent A. attenuata but has upward-curving leaf tips that suggest flames. Hardy to about 25F.
A. 'Blue Glow'. Zones CS, TS; USDA 9-11. This compact, colorful cross between A. attenuata and A. ocahui grows 12 ft. tall and 23 ft. wide. It forms a solitary rosette of blue-green leaves edged in red and yellow and tipped with a short red spine; leaves seem to glow when back-lit. Hardy to at least 28F. In hottest locations, plants grow best with some shade.
A. chrysantha. Zones LS, CS, TS; USDA 8-11. Native to Arizona. Dense rosette to 3 ft. high, 5 ft. wide. Gray-green leaves have hooked spines along the edges and a sharp spine at the tip. Golden yellow flowers are borne on short branches along upper part of a stalk that reaches 12 20 ft. tall.
A. colorata. Zones LS, CS, TS; USDA 8-11. From Mexico. Rosette of broad, flat, spiny-edged, bluish leaves grows slowly to 3 ft. high and wide. Each leaf is tipped with a wickedly sharp 2-in. spine; cut off these spines if you plant this species near a walkway. Reddish orange to yellow flowers on a stalk to 10 ft. tall. Takes heat and cold well.
A. filifera. Zones LS, CS, TS; USDA 8-11. Mexican native. Rosettes are less than 2 ft. wide; leaves are narrow, dark green, lined with white, and edged with long white threads. Spreads fairly quickly to form a clump of tight rosettes. Adapted to very hot, dry sites; hardy to 17F.
A. guttata 'Jaguar' (Manfreda guttata 'Jaguar'). SPOTTED FALSE AGAVE. Zones LS, CS, TS; USDA 8-11. Native to Mexico. Forms a 2-ft.-tall by 3-ft.-wide rosette of lightly toothed, 2-in.-wide, deep green leaves heavily spotted with purple. Tall spikes of spidery, fragrant flowers in summer. Plants form new clumps by offsets.
A. havardiana. Zones US, MS, LS, CS, TS; USDA 6-11. Cold-hardy native of West Texas and New Mexico. Silvery gray leaves form a sturdy rosette 2 ft. tall and 23 ft. wide. Spines along leaf edges and at tips. Greenish yellow flowers with a reddish tinge are borne on a stalk to 15 ft. tall. Produces the occasional offset but is not really a spreader. Hardy to 0F in dry gardens.
A. maculosa (Manfreda maculosa). TEXAS TUBEROSE. Zones MS, LS, CS; USDA 7-9. Native to southern Texas, northern Mexico. Forms a 1-ft.-tall and 2-ft.-wide rosette of fleshy, narrow, 6- to 12-in.-long leaves in deep green blotched with purple. During summer, 2- to 3-ft.-tall flower stalks bear fragrant, tubular, 2-in.-long blossoms in creamy white aging to purple; long stamens give them a spidery look. Leaves die back in winter but reappear quickly in spring. Plants form new clumps by offsets.
A. mitis (A. celsii). Zones CS, TS; USDA 9-11. From the cloud forests of Mexico; tolerates more humidity than other agaves. Apple-green to blue-gray leaves with small, neat teeth form a rosette to 2 ft. tall and wide. Spreads by offsets to form small colonies. Blossom stalk to 5 ft. tall bears yellowish green to purplish flowers. Provide regular summer water and protection from frost in winter. Needs afternoon shade in hottest areas.
A. ocahui. Zones LS, CS, TS; USDA 8-11. Native to the Sonoran desert. This adaptable species forms a solitary, symmetrical rosette about 2 ft. tall and 3 ft. wide. The straight, narrow, dark green leaves have smooth edges and a sharp but flexible terminal spine. Leaf margins have a thin, dark red, fibrous border that detaches from the mature leaves. Yellow flowers decorate a delicate bloom spike to 10 ft. tall. Plants thrive in sun or shade in any well-drained soil and are hardy to 15F. Good in pots.
A. parryi. Zones US, MS, LS, CS, TS; USDA 6-11. Native to southwestern U.S. and northern Mexico. Perhaps best known by its two similar botanical varieties, A. p. parryi and A. p. huachucensis, which produce rosettes resembling giant artichokes 12 ft. high, 22 ft. wide. Both spread by offsets; both have thick blue-green leaves tipped with long spines. A. p. parryi is quite cold hardy, and its leaves and spines are smaller than those of A. p. huachucensis. When plants are about 20 years old, they produce yellow flowers on a stalk to 15 ft. Both grow well in containers, thrive in partial shade. A. p. truncata (Zones MS, LS, CS, TS; USDA 7-11) grows only 1 ft. tall and wide but multiplies into a clump several feet across.
A. parviflora. Zones MS, LS, CS, TS; USDA 7-11. Native from southeastern Arizona into Mexico. One of the smallest agaves, producing a rosette 6 in. high, 9 in. wide; spreads by offsets. Dark green leaves with white markings; pale yellow flowers on a stalk to about 3 ft. or a little taller.
A. salmiana. Zones LS, CS, TS; USDA 8-11. From Mexico. Rosette to 34 ft. high and wide, spreading by offsets. Broad, dark green leaves have smooth edges and spiny tips. Blossom stalk grows 1525 ft. tall; red buds open to greenish yellow flowers. Dramatic plant for large landscapes. 'Butterfingers' has creamy yellow leaf margins.
A. undulata 'Chocolate Chips' (Manfreda undulata 'Chocolate Chips'). Zones MS, LS, CS, TS; USDA 7-11. Native to Mexico. Broad, spreading rosette of deep green, wavy-edged, narrow, cupped leaves covered with purplish brown spots and lightly toothed. Grows about 12 in. tall and twice as wide. Summer flower spikes, up to 3 ft. tall, are lined with dramatic green blooms with long, spidery purple stamens. Great in containers.
A. univittata (A. lophantha). Zones LS, CS, TS; USDA 8-11. From Mexico. To 2 ft. high, 4 ft. wide; may spread by offsets to form colonies. Glossy, sword-shaped leaves are dark green with a lighter green stripe (most noticeable in spring and early summer) running down the center. Leaf edges and tips are very spiny. Pale green blossoms on a 6- to 10-ft.-tall stalk. 'Splendida' features a prominent light green stripe down the center of each leaf that endures all season; plant grows 1 ft. tall and 12 ft. wide. 'Quadricolor' adds a striking cream edge to the variegated 'Splendida', but is best grown in Coastal South and Tropical South only.
A. variegata (Manfreda variegata). Zones LS, CS, TS; USDA 8-11. Native to southern Texas, eastern Mexico. Spreading ground cover for dry soil. Forms a mat to 1 ft. tall and 4 ft. wide. Slender, purple-mottled green leaves to 1 ft. long. In summer, 4-ft.-tall blossom stalks bear exotic-looking flowers to 1 in. long that resemble a green-and-maroon version of tuberose blooms.
A. victoriae-reginae. Zones LS, CS, TS; USDA 8-11. Mexican species, forming clumps only a foot or so across. The many stiff, thick leaves are 6 in. long, 2 in. wide, dark green with narrow white lines. Slow growing; will stand in pot or ground 20 years before flowering. Blossoms are greenish, borne on tall stalks. 'Kazo Bana' (Zones CS, TS; USDA 9-11) sports golden edges on the leaves, in addition to the white stripes. Grows slowly to 10 in. tall and 18 in. wide.
A. virginica (Manfreda virginica). FALSE ALOE, RATTLESNAKE MASTER. Zones US, MS, LS, CS; USDA 6-9. Native from Maryland to Missouri, south to Texas and Florida. Spreads by rhizomes to form colonies. Dark green leaves may be mottled or striped with red; they grow 2 ft. long and only 2 in. wide. Greenish yellow, spicily fragrant flowers appear atop 6-ft. spikes in summer. Dry seedpods rattle with loose seeds.