May 24 column: Clematis

Here is a link to my column in today’s edition of The Spokesman-Review: Regal climber. (or you can read my column lower in this post.) It is a feature story on one of the most-loved vines for the garden, the clematis.

For the article, I interviewed Carol Newcomb, who is the owner of Northland Rosarium (later renamed to Rosarium Garden Center). She and her husband, Terry, grow all sorts of beautiful clematis. Most of them were just coming into bloom in their beautiful display gardens during my visit.

While I was there last week, I took photos of some of the clematis vines that were blooming. Aren’t they just the most breathtaking flowers?

Clematis garden column:

by Susan Mulvihill

It has been called “the queen of vines.” It’s known for its lush foliage and wide variation in flower colors and sizes. The clematis has easily earned that title and a spot in the garden.

Carol Newcomb enjoys sharing her love of clematis (pronounced CLEM-a-tis or cle-MAT-is). As owner of Northland Rosarium, she carries about 50 varieties of these amazing vines and knows firsthand how rewarding it is to grow them.

“Clematis is a large, diverse group of plants that will grow from 12 inches up to 20 feet. It comes in all sorts of different colors,” she said. “No matter what your space, there’s one that will fit it.”

While some might think they’d be challenging to grow, Newcomb says that’s not the case at all.

Clematis cultivation

“They’re very easy vines to grow,” she explained. “It’s said they like their head in the sun and feet in the shade, which is very true. They like some sun — although will tolerate a lot of shade — and like their root system to stay cool.”

This can be accomplished by placing mulch over the root area. It also helps to plant a perennial or rose at the base of the plant to shade it a bit.

Clematis can be planted throughout the garden season. Spring is considered best because it gives them the opportunity to become established well before fall. Most clematis are in USDA hardiness zones 3 and 4, so they thrive in the Inland Northwest’s climate.

“The plants can live up to 50 years. That means it’s important to get them off to a good start,” Newcomb advised. “They like a rich growing environment, plenty of water and they like to be fertilized.”

Provide support

When selecting a location for a clematis vine, remember they will need to grow up on some type of support. They climb by wrapping their petioles, or leaf stalks, around a support. Ones that are the diameter of a pencil work best. Newcomb suggests using cattle panels, fishing line or wire. Some gardeners grow clematis on a fencepost, arbor, or through a tree or rose. All of these methods add a vertical element to the landscape.

Plants should be fertilized twice during the growing season. First, in the spring when tidying up the garden and again in midseason. Newcomb suggests doing the second fertilization before the end of July. That gives plants a chance to use up the rest of the fertilizer before the fall. She advises against feeding them while the plants are flowering. This can encourage green growth at the expense of blooms.

Newcomb recommends organic fertilizers, alfalfa meal and compost, or balanced fertilizers such as 20-20-20 or 10-10-10.

When to prune them

Knowing when to prune a clematis vine can be confusing. Most clematis have been divided into three main groups that identify bloom time and when to prune them. There are also herbaceous clematis which die back to the ground every year.

Refer to the accompanying box for an explanation of each group and how to prune them.

Even so, Newcomb doesn’t want gardeners to be fearful of pruning their vines. “You will never kill a clematis by pruning it wrong,” she said. “You’ll just change when they bloom.”

CLEMATIS GROUPS
The following are Carol Newcomb’s descriptions of each clematis group. This includes, when they bloom, when to prune, and some of her favorite varieties within each.

• Group One – Vines bloom in early spring, typically April and May, on last year’s wood. Tidy the plant in the spring, shake off old leaves and remove any broken branches. Guide new growth into position and do any needed pruning after the bloom is finished.
Carol’s picks: Constance, Pink Flamingo, Stolwijk Gold, Frances Rivis, Purple Spider, Blue Bird.
• Group Two – Vines bloom later in the spring and early summer. They are on last year’s wood and some of the new growth as well. Prune in spring before the new growth begins: look for healthy buds and trim just above them. Trim away any damaged or crowded branches.
Carol’s picks: The President, Diamond Ball, Vyvyan Pennell, Guernsey Cream, Rhapsody.
• Group Three – Vines bloom on new wood. Before new growth begins in the spring, cut the vine to the ground as last season’s branches will be dead.
Carol’s picks: Clematis texensis Duchess of Albany and Princess Diana; clematis viticella Etoile de Violette; and small-flowered clematis Paul Farges.
• Herbaceous Clematis – Vines die back to the ground every year. All dead growth should be removed before new growth begins in the spring. Just as you would do with perennials each year.
Carol’s picks: Clematis integrifolia Blue Ribbons and Arabella.