The Clematis genus includes about 250 different species of perennial climbing plants that can vary greatly in their size, growth habit, flower characteristics and blooming season. Clematises are typically climbing vines that are extremely hardy, withstanding winter temperatures as cold as -35 degrees Fahrenheit. Although clematis plants are rather unattractive during the dormant winter season when they're bare of leaves and flowers, they bloom in lovely blossoms during other parts of the year. Hybrid clematis vines tend to have the best blooms, some of which are up to 10 inches across and are distributed throughout the vine.
Provide a climbing support for your clematis that has thin wires so that the plant can grip the structure with its twining petioles. Match up the size of the climbing support with the ultimate size of the clematis at maturity.
Water your clematis deeply to thoroughly soak the soil around the roots once every week from spring until fall when rainfall is less than 1 inch.
Mulch around the clematis vine to keep its roots and the soil cool, as well as to maintain soil moisture and control weeds. Spread a 2- to 3-inch layer of organic mulch around the base of the clematis plant. Add fresh mulch to maintain the depth of the layer once each year in late spring, after the soil has warmed up.
Feed your clematis once each year in early spring with ½ pound of a slow-release 15-5-5 NPK fertilizer formula. Spread the fertilizer granules on the soil over the entire root area of the clematis vine, up to 50 square feet of area around the plant.
Prune your early-flowering clematis vines once each year immediately after they're finished blooming and before August to remove all shoots that have bloomed and to control the vine's size. Prune large-flowered hybrid clematis plants in February or March to remove dead or weakened stems and to cut back all other stems to the top pair of large green buds. Prune late-flowering clematis vines in February or March to cut all the stems back to about 2 to 3 feet in height.