Clematis is often called the queen of vines, offering extraordinary beauty and presence in any style or size of garden.

These versatile plants can be grown as vines, shrubs and even as ground covers. With hundreds of varieties to choose from, there are colors, shapes and sizes to please any gardener’s needs.

It is best to purchase plants from specialty nurseries or garden centers. Try to choose ones that are container-grown and have two to three stems.

A site that receives at least five hours of sunlight daily is best. Arbors and trellises should be installed before planting to avoid disturbing the clematis roots after they are established.

Clematis can be grown in combination with many deciduous shrubs. The vine will freely scramble and twine through its branches, providing interest and color after the shrub has finished flowering. Shrub roses and clematis are perfect partners, but other shrubs, including viburnum and weigela, also work well. Avoid pairing clematis with hedges that require regular maintenance pruning or evergreens, as a vigorous vine will block some of the sunlight needed to maintain a healthy plant.

Before planting, soak the root ball in warm water for approximately 15 minutes while digging the planting hole. Dig a generous hole, at least two times the width and depth of the container. Amend with compost, as clematis thrive on organic matter. However, take care to add a layer of soil over the compost to avoid damaging or burning the roots.

If the plant is pot-bound, gently loosen the root ball. Place it in the planting hole so that the crown of the plant (where stems and roots meet) is 2 inches below the surface of the soil. Remove foliage from the base of the vine before burying the stems underground.

Planting clematis deeply will help to develop a healthy basal root crown of buds below the soil level. Most of these buds will remain inactive unless the plant is damaged later on in its life. Allow the clematis to grow freely, but do not allow it to flower the first year it is planted. The following spring, prune the stems 12 to 18 inches from ground level. This will encourage new shoots to develop from below the soil surface.

Once the clematis is established and is flowering, one of the most frequently asked questions is, how are they pruned? Clematis are classified into three groups based on the time of flowering.

Group 1 — Flower in spring on old wood. These plants require minimal pruning; simply remove any dead or damaged stems after flowering. Group 1 includes Clematis alpina, which bears smaller, pendulous flowers.

Group 2 — Produce two flushes of flowers, once in spring on old wood and again in late summer on the current season’s growth. They require light pruning to remove dead or weak stems in early spring and again after flowering. Heavy pruning will result in few flowers. Group 2 includes one of the most popular clematis cultivars, ‘Nelly Moser,’ which has large pale, pink flowers with a prominent dark pink central bar.

Group 3 — Flower in early summer on new wood. In the spring, prune back all stems just above the first live, swollen bud. This group includes ‘Jackmanni,’ well known for its large dark royal purple blooms.

Recommended mail-order nurseries include Joy Creek Nursery, Chalk Hill Clematis and Completely Clematis Specialty Nursery.

To learn more about gardening with clematis, attend the lecture “Growing and Designing With Clematis” by Maurice Horn, co-founder of Joy Creek Nursery, as part of the Western Pennsylvania Gardening & Landscaping Symposium. It’s scheduled for next Saturday at Chatham College. Information: 412-441-4442.

source : www.post-gazette.com