The Varieties of Coreopsis

USDA Zones 3 and 4

• Cold hardy in U.S. Department of Agriculture plant hardiness zones 3 and 4, the tall coreopsis (Coreopsis tripteris) grows as high as 8 feet. This form, like many coreopsis varieties, does well in poor quality soils, as long as the ground drains. Tall coreopsis blooms from July through September, generating a brownish central disk surrounded by yellow rays. Coreopsis Rosea "American Dream" is suitable for zones 3 and 4, growing to 24 inches and blooming in June, July and August. A cultivar of pink tickseed, American Dream possesses pink rays about a yellow disk.

USDA Zones 5 and 6

• Remove the spent flowers of Goldfink, a form of lanceleaf coreopsis (Coreopsis lanceolata) and the flowers will come back in bloom through summer. Flowering in late spring on the 10-inch tall perennial, the blooms are yellow and as wide as 2 inches. Goldfink grows safely in USDA zones 5 and 6. Use Sienna Sunset, a hybrid coreopsis, in containers on the patio. Zones 5 and 6 are the coldest regions where this flower survives. Sienna Sunset grows to 18 inches and features a burnt orange flower from June into September.

USDA Zones 7 and 8

• Coreopsis verticllata "Moonray" is a type of threadleaf coreopsis, with the needle-like leaves associated with this variety. It handles the warm zones such as USDA zones 7 and 8 with few problems. The yellow flowers are butterfly magnets. Threadleaf coreopsis normally is very drought-resistant and lives a long time, according to Perennial Resource. Plains coreopsis (Coreopsis tinctoria) is an annual used in mass plantings for its wonderful flowering effect. It easily grows in zones 7 and 8, developing to as high as 48 inches and producing yellow and red flowers from June into early fall. Plains coreopsis will generate enough seeds on its own to come back the next year.

USDA Zone 9

• Zagreb is a heat- and humidity-tolerant type of threadleaf coreopsis ideal for USDA zone 9. Zagreb grows to 18 inches, features brilliant yellow flowers similar to daisies and has a rhizomatous root system. This system generates new growth when you plant Zagreb in moist, fertile sites. Coreopsis auriculata "Nana" is a variety of ear-leaves tickseed for zone 9, growing to just 9 inches high. Its broad leaves are shiny green, and its May through June flowers bloom yellow. Use Nana as ground cover or plant this dwarf coreopsis cultivar along pathways.