How to Prune Your Vines
Vines are wonderful additions to the landscape, and come in many sizes and levels of vigor to fit almost any need. Because of their naturally informal habit, many vines need proper pruning to keep them under control and blooming profusely. Here is how you prune some of the most common vines. Note that the shorter the pruning instructions, the less fussy the plant is about simply being cut back where needed, as needed.
Large-flowered Clematis (groups I, II, III)
In most cases, pruning is not required for clematis except to remove dead or damaged stems. If you need to prune for size control, follow these guidelines:
Group I: These clematis are early spring bloomers and flower on older growth produced the previous year. Pruning is not required, but if you need to control them, prune these back as soon as possible after bloom and no later than the end of July. Do not cut into woody growth unless thinning is needed. Plants in this group include C. alpina, C. macropetala, C. armandii and C. montana.
Group II: Large-flowered hybrid clematis that bloom in late spring-early summer on short stems from the previous season's growth and often again in late summer on new growth. Prune in late winter-early spring by removing dead and weak stems, then cut back remaining stems to the topmost pair of large, plump green buds. This should be a fairly light pruning. Plants in this group include: 'Nelly Moser,' ‘Henryi’, ‘The President, ‘Belle of Woking,’ and others.
Group III: Plants in this group flower on the last 2 to 3 feet of the current season's growth. Some types begin blooming in mid-June and continue into the fall. To control size, cut each stem to a height of 2 to 3 feet in late winter. Plants in this group include: C. viticella, C. x jackmanii, C. terniflora, 'Royal Velours,' and others.
All types: Renovation pruning down to 6” of all the stems in late winter will refresh old, sparse, overly matted or poorly shaped clematis. However, if your clematis is from group I or group II, it will not bloom that year. It will be worth it if your clematis has become ugly. For group I and II, prune again the second year to about 3 feet. This will create a bushy, floriferous plant.
Sweet Autumn Clematis (Clematis terniflora)
See Group II above. Can be renovation pruned.
Armand's Clematis,Evergreen Clematis (Clematis armandii)
Unpruned, it scrambles through and over shrubs and small trees. It can cause damage by excessively shading its host. To control this aggressive vine, cut it back hard after flowering or in early spring. Can be renovation pruned.
Confederate Jasmine (Trachelospermum jasminoides)
Pinch the tips to stimulate lateral growth and prune lightly after flowering if necessary to restrain growth. Flowers best if pruning of old wood is kept to a minimum.
Carolina Jessamine (Gelsemium sempervirens)
Older vines that become top heavy or sparse can be pruned back to a few feet above ground level after flowering. Remove dead or broken branches and shape the plant lightly each year after bloom. If used as groundcover, mow every few years to maintain density.
Chocolate Vine or Fiveleaf (Akebia quinata)
Chocolate vine can kill of small trees or shrubs if left untended as its vines can overpower the smaller plants. Prune annually after blooming in the late spring. Remove suckers and climbing shoots from walls and cracks by hand. Either wrap them around the vine support or remove them by cutting them with clippers where they attach to the main vine. Remove main stem every few years to encourage new growth. Renovate by trimming all matted growth back to main stems.
Trumpet Creeper (Campsis radicans)
Blooms on new growth, so early spring pruning will not affect the flowering. Can be pruned hard. Vines must be grown on sturdy structures because mature plants produce considerable weight. Renovate by cutting back to 12”
Evergreen Honeysuckle (Lonicera sempervirens)
Blooms primarily on previous year's stems, so prune to shape after flowering. Thin occasionally as needed in spring to control crowded growth.
Goldflame Honeysuckle (Lonicera x heckrottii)
Goldflame honeysuckle flowers on new growth; prune in spring to keep flowers developing all over the plant and not just at the ends. For a bushier appearance, cut stems at random lengths so they develop new growth throughout the vine. Summer pruning to control vigorous growth will not harm honeysuckle.
Climbing Hydrangea (Hydrangea anomala subspecies petiolaris)
The best time to prune climbing hydrangea is after it flowers, but it can be shaped at almost any time from late winter to mid-summer. Regardless of when you prune climbing hydrangea, cut back the long shoots and those growing outward from the wall to just above a bud or leaf point.
Wisterias
Japanese Wisteria (Wisteria floribunda)
Japanese Winsteria requires pruning twice a year in late winter (March) and late summer (August) to encourage flower buds. Begin by identifying the thickest and oldest branches (the first-tier wood) that form the central architecture of the vine. Coming off of these are medium-thick branches (second-tier wood). These, in turn, produce lots of long, whippy stems springing outward (third-tier wood).
If the wisteria is congested, with too many medium-sized branches following and twisting around the heaviest first-tier wood, use the loppers to eliminate up to half of the second-tier wood (which will also remove the youngest wood springing from those sections). The second-tier branches tend to twist around older wood and some sections may be too closely bound together to allow removal, so cut as low down and close to the thickest, first-tier wood as you can. This will help to control the size and weight of the vine and improve its appearance when in leaf.
In winter, cut the youngest stems (third-tier wood) back to about eight inches (20 cm) in length, allowing three or four buds to remain. This will encourage the vine to turn these stubs into flower spurs. Be sure to keep any short (six- to eight-inch/15- to 20-cm) flower spurs already present. (You may not encounter any if the wisteria has never bloomed and this is the first pruning.) Pointed buds that lay flat against the wood produce foliage; slightly raised, plumper buds will be flowers. If flower spurs with buds are present, these will bloom and the reduced foliage won’t conceal them. If no flower buds are present, your pruning work this year will pay off in flowers next year.
Chinese Wisteria (Wisteria sinensis)
These vines bloom on old wood. Try pruning a couple of times each year (in early summer after blooming, and during dormancy in winter) to stimulate budding for next year. Regarding the latter pruning, NC State University advises that you "prune back old growth to three to four buds in late winter." These vines bloom on old wood.
American Wisteria (Wisteria frutescens)
Blooms on current season's growth. Trim lightly after flowering, to encourage a second flush of blooms in the summer. Prune again in late winter to shape and remove undesired growth.
Cross Vine (Bignonia capreolata)
Prune after flowering if needed. It is forgiving of any shaping required. Can be renovated by cutting back hard in early spring.
Lady Banks Rose (Rosa banksiae)
Lady Banks blooms on old wood, so be careful not to over-prune the older branches. Prune after flowering if needed.