Trumpet Vine, Wild Grape, Climbing Hydrangea

(Question)

I have 3 vines I would ideally like to remove or at least reduce as much as possible. How do I prune without encouraging too much growth?
Zone 6 (close to the bluffs on lake Ontario), soil is clay
1) trumpet vine on a pergola in sun, 10 yrs old
2) climbing hydrangea on brick in shade, 3 yrs old
3) wild grape on a wood fence in shade, 3 yrs old
thank you.

(Answer)

Trumpet vine ( Campsis radicans) vines are fast-growing vines known for their trumpet-shaped flowers which will attract hummingbirds to your garden however, without regular pruning this vine can reach 30-40 feet in just one season. Pruning trumpet vines encourages new growth by redirecting energy and revitalizing the vine. Trumpet vines bloom in midsummer on the current year’s growth; as a result severe fall pruning will not limit the vine’s flowers the following summer. In fact, pruning trumpet vines properly encourages the plants to produce more flowers every summer. Once all the flowers have dropped for the season, the trumpet vine begins to enter dormancy, making it the perfect time to trim it down. Trimming the branches in the autumn also prevents seedpods from dropping and starting new vines. Begin by removing old stems that have become spindly or weak. Cut the top stems down to 25.4 cm to encourage new, fuller growth. Make sure to leave at least 3-4 buds per stem and only remove about 1/3 of the wood at a time. If you remove more than that, you run the risk of shocking the vine.

A climbing hydrangea flowers on old wood. That is to say, flowers will only grow on branches formed in the previous year. Cutting back hydrangea vines is best done immediately after flowering in August or September, before new buds appear. Otherwise, you risk cutting off flower buds that appear soon after flowering, thus drastically reducing development of new blooms for the upcoming year. Branches that are just too long can be cut right back to the main stem and this way you keep your climbing hydrangea looking neat and tidy.

Pruning an old, overgrown grapevine requires a form of severe pruning that removes about 90 percent of the plant’s total growth. Severe pruning directs the plant’s roots toward producing fresh new growth. Cut back the main trunk to 5 feet tall. Remove all canes that are smaller in diameter than an average pinkie finger, or which show signs of cracking and have weak attachments to the trunk. Remove all the canes older than 2 years where they attach at the vine. Canes older than 2 years don’t produce fruit. Make the cuts at a 45-degree upward angle to help protect the canes from rain. Choose two to four of the newest fruiting canes,then cut these back until there are about 15 buds on the cane.