Should clematis be trimmed back every year or should you just leave the old growth?

Is there anything I can do to encourage their spreading habit?

Should clematis be trimmed back every year or should you just leave the old growth?
According to Garden Gate magazine there are three types of Clematis: A, B, and C. How to prune depends on which type you have. Group C gets cut down near the ground in the Spring. Group B gets trimmed at the tips and thinned out where vines overlap. Also remove dead and broken branches. Group A never gets trimmed all the way down, just cut back the tips.


Good luck!
Reply:I normally trim the runners close to the base, but leave the main vine.. letting shoots grow further up... the whole thing looks dead and horrible in winter but comes back beautifully in spring... also check paul james website 'gardening by the yard' it's packed with awesome info for the green thumbers !