Vines are plants whose long stems twine, cling or wrap themselves around wall, fences, trees, arbors or other garden structures. Vines are vigorous growers and over time will become to a tangled mass of stems and leaves if they are not properly pruned and given adequate support. They require regular pruning to keep them healthy, profuse bloomers and under control. Pruning vines also allows light and air to reach the plant's interior.
Some general rules for pruning vines: Vines which are grown for their foliage, such as English ivy (Hedra helix), which climb by using aerial rootlets and Virginia creeper (Parthenocissus quinquefolia) which have little suction cups that grab onto walls and other surfaces can be pruned any time during the season. Flowering vines are pruned according to when they flower. Theses include the twining and wrapping vines Wisteria and honeysuckle (Lonicera) as well as those which climb using tendrils, such as Clematis and passionflower (Passiflora).
Spring-flowering vines are usually pruned, like spring-flowering shrubs, immediately prior to flowering. Summer blooming vines produce their blooms on the current years growth and should be pruned after flowering or in very early spring, during their dormant season. An exception concerns vines that produce ornamental or edible fruits. These should be pruned spring, or the fruit crop will be lost.
Since vines will grow on indefinitely, pruning is essential. More often than not vines which are left to grow will creep into places they don’t belong, such as windows and doors. Some vines can become too heavy for the structure they’re attached to resulting in damage.
When pruning vines, remove any dead, damaged, tangled or diseased stems and stems which are growing in the wrong direction. Be sure to direct its growth away from windows and doors. Always cut back to a lateral shoot or bud that is pointing in the direction you want the vine to go. Also, prune back to healthy wood and give the plant a cut cleanly.
Twining vines tend to grow from upper buds and tend to lose their lower leaves. Stems with sparse foliage should be pruned back to promote new, low-growing foliage. To further encourage growth on the lower portion of the vine it should be trained horizontally to force upward growth to develop from lateral shoots. Moderate pruning in the first few years will also encourage low branching.
Be sure you have adequate space as well as sturdy structures frequent pruning may become necessary. Old wisterias can produce primary stems the size of tree trunks and have been known to pry off drainpipes and gutters.
New vines often need to be trained in order to begin climbing a garden structure. Use a short piece of string, netting, or stake to provide guidance to the lower portions of the arbor, trellis, etc. As long as there is something sturdy to mount, true vines can do it alone, or with minimal help. Climbing roses (Rosa) neither cling nor twine and can't grow up an arbor without assistance.