The Clematis

By: Kit Smith

UCCE/El Dorado Master Gardener

 

One of my favorite flowering plants in my garden is my clematis. It is a beautiful attention getter which takes very little care. There are over 200 species of clematis. The main differences between these plants involve when the clematis blooms and whether it blooms on old or new wood. Because clematis can remain undisturbed for years, proper planting can get your clematis off to a good start and proper care can keep it blooming for years.

           

            PLANTING - Site selection for clematis is important.  The clematis should be planted in rich cool well-drained soil with its “head in the sun and feet in the shade.” Plant them 18–24 inches apart, out of drying winds or direct sun. Loosen the roots carefully when planting. Typically, the clematis does not have a large root system, and its shallow roots can be easily damaged. Mulch around your clematis to keep its roots cool in the summer and insulated from excel cold during the winter. Consistently water the clematis as the roots store energy for winter.

            SUPPORTING - Stake it. Your fast growing clematis vine will need support as it climbs and wraps its petioles around the nearest narrow object.  The clematis will entangle itself in its own stems. The clematis is a good plant for an arbor as it is not a broad reaching plant. Pinch back fast-growing tips to allow the roots to balance with the top growth and to form a well-furnished base.

            FEEDING - Fertilize your clematis in fall with compost and with rock phosphate, well-watered in to improve the color of the blossoms in spring. Don’t fertilize after mid-summer to slow the new growth and to toughen up the wood that is already there before the cold arrives. Add lime only where a soil test indicates there is a calcium deficiency in the soil.  The clematis will bloom 4-5 inch flowers five months after planting, and the flowers will be followed by fluffy seed pods.

            PRUNING - Correct pruning of your clematis depends upon the species. If you do not know which type you have, watch it for a year. There are three different groups of clematis. One group flowers on old wood in spring, another on spring wood in summer, and the third on spring wood in fall. 

            The spring flowering clematis only blooms on old wood. It is very hardy, and you can chop this one way down to a pair of fat, healthy buds that are about 12 inches from the ground or 15-20 inches if plant is old and thick. Prune one month after flowering.

            The summer and fall blooming clematis bloom on spring wood, so they should be pruned following flowering or in early spring as the buds swell to restrict sprawl, preserving main branches.

            All clematis will bloom, even if you never cut anything. If you should have pruned, but you did not, then the flowers will be smaller and high on the plant. If you pruned too vigorously or you pruned at the wrong time, the plant will recover eventually and may even be stronger in the long run.

 

You’ll find some tried and true varieties of clematis at our local nurseries, with more exotic varieties available through mail order and on-line sources.  For more information on pruning clematis, check out a previous article listed on the Master Gardener website at http://ucce.ucdavis.edu/files/filelibrary/616/20705.doc.