These sturdy plants are grown for their familiar, colorful blooms; most are prime subjects for cut flowers. Plants are tough and widely adapted. Perennial kinds spread rapidly and may become invasive. Tall kinds are not for tidy gardens; may need staking. All bloom in summer and fall.
H. angustifolius. SWAMP SUNFLOWER. Perennial. Zones US, MS, LS, CS; USDA 6-9. Native to eastern U.S. Grows 512 ft. tall, 34 ft. wide. Bears narrow, 6-in. leaves and sheaves of bright yellow, 2- to 3-in. daisies with dark brown centers. Likes ample moisture but adapts to ordinary garden conditions. Sometimes confused with H. salicifolius but blooms 2 weeks later. Spreads rapidly by rhizomes. Very showy. 'Gold Lace' has the bright yellow flowers of the basic species, but it tops out at 56 ft. tall and spreads less vigorously. 'Mellow Yellow' has pale yellow blossoms.
H. annuus. COMMON SUNFLOWER. Annual. Zones US, MS, LS, CS, TS; USDA 6-11. The wild ancestor of today's familiar sunflowers is a coarse, hairy plant with 2- to 3-in.-wide flowers, native to much of the central U.S. and southward to Central America. It is the state flower of Kansas and the only plant native to the contiguous 48 states to have become an important agricultural commodity. It has been bred to produce giant plants as well as a host of smaller (but still significant) selections for garden decoration and cut flowers. For children, annual sunflowers are easy to grow and bring a sense of great accomplishment. Sow seeds in spring where plants are to grow. Large-flowered kinds need rich, moist soil. People eat the roasted seeds; birds enjoy the raw ones in fall and winter.
Best known among the giant forms are 'Mammoth Russian', 'Russian Giant', and 'Sunzilla'. They grow 10 ft. (possibly 15 ft.) tall and 2 ft. wide, typically producing a single huge head (sometimes over a foot across) consisting of a circle of short yellow rays with a brown central cushion of seeds. 'Kong' is similarly towering; 'Sunspot' carries 10-in.-wide flower heads on 2-ft.-high plants. 'Maya' produces multiple 45 in. blooms of golden yellow and lots of seeds for goldfinches.
Sunflowers for cutting come on compact, branching plants and bear 4- to 8-in.-wide blooms in a rich variety of colors. They fall into two basic categories: pollen-bearing types and pollenless ones. Kinds with pollen include 'Del Sol', early-blooming, yellow, 5 ft. tall; 'Indian Blanket', red with yellow tips, 45 ft. tall; 'Italian White', creamy yellow to near white, 5 ft. tall; 'Lemon Eclair', light yellow, 46 ft. tall; 'Moonshadow', pale yellow to cream, 4 ft. tall; 'Ring of Fire', petals dark red at base and golden yellow at tips, 56 ft. tall; and 'Soraya', 56 ft. tall, with heavy production of rich orange flowers. 'Teddy Bear', only 112 ft. tall, has fully double, 6-in.-wide flowers that look like pompons.
Kinds without pollen, classified as H. xhybridus, have the advantage of not shedding on tabletops. Many have a branching growth pattern, producing several flowers on each plant. Look for Large Flowered Mix, yellow, red, and bronze, 610 ft. tall; 'Bright Bandolier', yellow-and-mahogany bicolor, 57 ft. tall, branching; 'Cinnamon Sun', cinnamon-bronze, 47 ft. tall; 'Moulin Rouge', burgundy, 56 ft., branching; 'Peach Passion', peachy yellow, 4 ft. tall, branching; Pro Cut series, 4 ft. tall, single stem; 'Prado Red', deep garnet, 3124 ft. tall, branching; 'Strawberry Blonde', red with yellow tips, 67 ft. tall, branching; 'The Joker', burgundy with yellow tips, 56 ft. tall, single stalk; 'Valentine', light yellow, 45 ft. tall, branching; and 'Velvet Queen', combination of bronze, burgundy, chestnut red, and mahogany, 68 ft. tall, branching.
H. atrorubens. DARK-EYED SUNFLOWER. Perennial. Zones US, MS, LS; USDA 6-8. Native to southeastern U.S. Grows 56 ft. tall, not quite as wide, with coarse, bristly foliage and 2-in. yellow flower heads centered in dark purple. 'Monarch' has semidouble flowers somewhat resembling the quilled flowers of a cactus-form dahlia.
H. 'Lemon Queen'. Perennial. Zones US, MS, LS, CS; USDA 6-9. Selected from a hybrid of two species native to the U.S., this stately plant grows 68 ft. tall, 23 ft. wide. Numerous pale yellow, brown-centered, 2-in. flowers appear in late summer. Perfect for back of casual border or in combination with large ornamental grasses. Takes moist or dry soil. Does not require staking, provided soil is not too rich and plants are not overfertilized.
H. maximilianii. MAXIMILIAN SUNFLOWER. Perennial. Zones US, MS, LS; USDA 6-8. Native to central and southwestern U.S. Clumps of 10-ft. stems clothed in narrow, 8- to 10-in. leaves and topped with narrow spires of 3-in. yellow flowers. Spreads to 3 ft. wide.
H. microcephalus. SMALLHEAD SUNFLOWER. Perennial. Zones US, MS, LS, CS; USDA 6-9. Native from New Jersey to Florida. To 36 ft. tall, 23 ft. wide. Lance-shaped to ovate 3- to 4-in.-long leaves. Clear yellow, 1- to 112-in. flowers.
H. xmultiflorus. Perennial. Zones US, MS, LS; USDA 6-9. Hybrid between H. annuus and a perennial species. To 5 ft. high, 2123 ft. wide, with thin, toothed, 3- to 8-in.-long leaves and numerous 3-in.-wide flower heads with yellow centers. Excellent for cutting. Flowers of 'Capenoch Star' are single, lemon-yellow with a large central brown disk. Recommended double-flowered types include bright yellow 'Flore Pleno', golden yellow 'Loddon Gold', and golden yellow 'Sunshine Daydream' (with numerous small blooms that resemble dahlias).
H. salicifolius. WILLOWLEAF SUNFLOWER. Perennial. Zones US, MS, LS, CS; USDA 6-9. Native to the central U.S. Grows 68 ft. tall and 3 ft. wide, with narrow, gracefully drooping leaves to 8 in. long. Stems are topped by profuse 2-in. yellow flowers with purplish brown centers. Looks somewhat like H. angustifolius but leaves are narrower. 'First Light' is compact at 34 ft. tall and wide, and 'Low Down' is smaller still, growing 11 ft. tall and 2 ft. wide.
H. tuberosus. JERUSALEM ARTICHOKE. Perennial. Zones US, MS, LS, CS; USDA 6-9. From eastern and central North America. Also grown as a commercial crop; tubers are edible and sold in markets under the name 'sunchokes'. Grows 610 ft. tall, 3 ft. wide, with bright yellow flower heads. Oval leaves 8 in. long. Spreads readily and can become a pest. Best to harvest tubers every year and save out two or three for replanting. If controlled, makes a good, quick temporary screen or hedge.