How Many Clematis Plants Will Cover a Six-Foot Trellis?

Location

• Pick a trellis site suited to clematis requirements. Once established, they don't like to be disturbed. A sheltered location with at least six hours of full sun plus cool, moist shade for the vine's roots is ideal. Annuals or perennials at the vine's base will help shade roots. For dark-colored blooms, filtered shade during the heat of the day helps prevent colors from fading and keeps flowers looking their best. Take time to get your location right. Improper locations can leave the vine stressed, susceptible to attack by insects and disease and unable to fulfill its potential to cover your trellis with flowers.

Culture

• For healthy roots and robust growth, clematis prefer rich, well-drained, evenly moist soil with neutral pH. As an added measure, plant your clematis so two buds are 1 inch below the surface. In the event your vine is stricken by pests or wilt, it can come back from the roots. Mix in liberal amounts of compost at planting, and follow through with annual applications to keep your clematis well fed. Keep soil consistently moist -- never soggy. Mulch around the base to keep roots cool. During its first year, your vine's energy will be devoted to establishing a strong root system to support it in future years. The second year, you'll see more growth. The third year should bring the cloud of flowers you desire.

Growth Type

• Clematis varieties fall into three general categories based on their growth. These in turn determine when your vine should be pruned to promote strong growth and maximize blooms. Early-flowering clematis bloom on old vines grown in previous years. Prune these only as needed for shaping. Mid-season varieties flower on old wood and new. Some bloom all summer; others bloom in late spring with another flush in fall. Prune these right after flowering, before new flower buds have time to form. Late-blooming varieties flower only on new vines produced that season. In late winter, prune away all the previous year's vines so energy is directed into vigorous new growth. Pruning appropriately helps ensure bountiful blooms for your trellis.

Companions

• Even though one mature clematis can cover a trellis alone, don't limit yourself to just one. Clematis do well when planted with companions, whether other clematis or different types of climbing flowers. Rather than a single vine with limited bloom time, plant two or three clematis on your trellis so complementary flowering continues from spring through fall. Clematis also pair beautifully with climbing roses. Again, you can use one clematis or up to three. Always fasten your trellis to a supporting structure, allowing several inches behind it for air circulation. Climbing vines need sturdy support to protect them from being dislodged by weight or winds.