Climbing hydrangeas have charming lacecap flowerheads made up of a disc of tiny, tightly packed flowers surrounded by a ring of larger blossoms. These lovely blossoms have an old-fashioned appeal, and when seen on a background of large, lush vines they are stunning. This article explains what to do when your climbing hydrangea fails to bloom.
When Does Climbing Hydrangea Bloom?
Climbing hydrangea blooms in late spring and summer. After a season or two comes and goes without a bloom in sight, gardeners may become worried about their vines. Take heart, because in most cases, there is nothing wrong. These vines are notoriously slow to become established and produce their first flowers. In fact, several seasons may come without blossoms. Rest assured that they are worth the wait.
Tips on Getting Climbing Hydrangeas to Bloom
If you become concerned about your climbing hydrangea when it fails to flower, take a look at this checklist of potential problems:
A late frost can damage buds that are on the verge of opening. You may want to try providing protection when a late frost threatens. A tarp or blanket thrown over the vine is enough to protect the plant from a light frost.
Vines that run along the ground won’t bloom. Attach the vines to a strong supporting structure.
Branches that stray from the main part of the plant use energy and don’t add to the appearance of the vine. They also add lopsided weight that may pull the vine away from its supporting structure. Remove them back to a main branch so the plant can focus its energy on upward growth and flowers.
When a climbing hydrangea won’t bloom, it’s sometimes the result of too much nitrogen fertilizer. Nitrogen encourages hydrangeas to put on a lot of dark green foliage at the expense of flowers. One to two inches of compost applied in a layer over the soil contains all the nutrients a young hydrangea vine needs. Once it’s established and growing well, you don’t need to fertilize at all. Lawn fertilizer is high in nitrogen, so keep it away from your hydrangeas.
You’ll have a hard time getting climbing hydrangeas to bloom if you’re pruning at the wrong time of year. The best time is immediately after the blossoms begin to fade. The buds for next year’s blossoms begin to form about a month after the flowering period. If you prune late, you’ll be clipping off next year’s blooms.