THE QUEEN OF CLIMBERS

The Queen of Climbers…could there be a better name for the Clematis? This elegant  perennial is prized for its blooms and feathery fruit. Even on the prairies, Clematis are renowned for their spectacular display of flowers in an array of different colours. However, questions often arise regarding the durability of these climbers in the prairie climate. Most often prairie nursery growers divide clematis varieties into hardy and tender groupings based on their parentage and origin. It is not unusual for the above-ground growth of tender varieties to be killed in late fall, with new growth emerging the following spring from buried, dormant buds.

In this brief article I would like to highlight three early, “small”-flowered clematis varieties developed in Manitoba by the late Dr. Frank Skinner. Frank Skinner was one of a few plant breeding pioneers that left an indelible mark on horticulture in the Canadian prairies and beyond. He accomplished a great deal in his lifetime and left many ideas for the next generation to pursue. One of Skinner’s breeding objectives was to develop ornamental climbers that would be cold hardy in zones 2 & 3.

While Skinner’s work with ornamental climbers is best represented by his famous Dropmore Scarlet Honeysuckle, he also had an interest in the hybridization of Clematis. In his book “Horticultural Horizons”, Skinner states “Much time and thought have been spent at Dropmore in an endeavour to raise large flowered Clematis hybrids that would be hardy without protection in our trying winters.” The following three varieties are hardy and undemanding, perfectly suited for the beginner that longs to enjoy the beauty of a clematis without the often attached challenges.

Blue Bird Clematis is an early flowering clematis variety known for its beautiful, lavender-blue flowers. The semi-double flowers are large and open, the result of crossing Clematis alpina with C. macropetala. The four twisted, outer sepals are mauve blue while the inner staminodes are slightly paler, giving the illusion of a blue bird in flight. The nodding flowers are produced in May and June, followed by equally ornamental seed heads that initially have a silky texture. Blue Bird Clematis is a very hardy plant with many possible uses in the landscape including climbing fences and walls or assuming a prostrate position over rocks.

Rosy O’Grady Clematis is another early flowering hybrid from a cross between Clematis macropetala and Clematis alpina. The semi-double, nodding flowers of Rosy O’Grady appear rose pink in colour with intense purple veins etched on the outside of each sepal. The sepals curl back at the edge to show a pale pink underlay of staminodes. Peak flower production occurs in May and June, however new shoots may continue to flower throughout the summer. The flowers are followed by fluffy seed heads that add attractiveness during the residual of summer. Like Blue Bird, Rosy O’Grady is multipurpose, well suited as a climber or groundcover. In 2002, Rosy O'Grady won an AGM (Award of Garden Merit) from the Royal Horticultural Society.

White Swan Clematis is a final example of Skinner’s efforts to combine the beauty of Clematis macropetala with the cold hardiness associated with other species. White Swan was a second generation seedling from a cross between Clematis macropetala and Clematis sibirica. This hardy vine has beautiful creamy white flowers about 5 inches in diameter, larger than its C. macropetala parent. The combination of nodding flowers and twisted white sepals produces an angelic floral display. White Swan also flowers in May and June.

TIPS FOR GROWING CLEMATIS

Clematis prefer moist, alkaline soil with good drainage. A southern exposure that provides ample sunlight is an ideal planting location. Clematis take up very little soil space and are extremely vigorous in growth. Plants should be watered at least once a week during the first few seasons, especially in dry periods. Shortly after planting, clematis should be pruned back to 12” to encourage strong bushy growth at the base.

When planting clematis be sure to include a strong trellis or netting for climbing. Remember that clematis canes must be firmly tied to the climbing support. Clematis should be planted at least 30 cm out from house walls. With a proper trellis or support, clematis will even grow in containers.  When selecting your container avoid metal or black pots that attract heat.  You may wish to add a trailing perennial at the base.

Clematis prefer growing locations where its roots can be kept cool. Small plants such as Lily of the Valley, or Heartleaf Bergenia should be used to shade the base of Clematis vines. Alternatively, gardeners may choose to place ceramic tiles around the plant to protect the root zone from higher temperatures.