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Hydrangea Pruning
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Date Posted: Wed, Jun 04 - 1:52 am
- Hello! My hydrangeas need some help. I inherited them with my new to me house in late fall, so this spring was my first opportunity to prune. They were already overgrown from the past owners. For the big leaf hydrangeas: I missed the fall pruning, so these haven't had a haircut since who knows when. The branches are getting weighed down from the weight of the flower and leaves, and the plant is very leggy. Should I try and start selectively and slowly clipping them back now or wait until they're done blooming and do it one big chop? If now, do I cut the old leggy wood back, or just the new green branches that are stemming from the old leggy wood (the two blooms on the top of the left bush are an example)? For the panicle hydrangea in the middle: I cut what I thought was way back this spring, but clearly not enough! Should I be trying to selectively trim some of this back now or bite the bullet and wait until spring and do a big chop? It's so tall and it's only May! Thank you!
- Thanks for reaching out—and congratulations on your new home and garden! It sounds like you’re giving your hydrangeas some thoughtful attention, which they’ll definitely appreciate. The blooms are beautiful! Here’s a breakdown of how to approach pruning both your bigleaf hydrangeas (Hydrangea macrophylla) and your panicle hydrangea (Hydrangea paniculata): Bigleaf Hydrangeas : These bloom on old wood, meaning the flower buds for this summer formed last year. That’s why heavy spring pruning can often result in fewer blooms. Since yours are blooming now, I'd recommend that you hold off on major pruning until after they finish flowering—typically by mid to late summer. Then you can: Remove about 1/3 of the oldest, leggiest stems at the base to encourage new growth from the bottom and lightly shape the plant by shortening stems that look untidy or weighed down. Avoid pruning after August, however, as that risks cutting off next year’s flower buds. In the meantime, if any branches are flopping badly or blocking paths, you can do a light, selective trim now—just avoid heavy cuts that remove flower buds. Panicle Hydrangeas: These bloom on new wood, so you have more flexibility with timing. You’re absolutely right that they can grow quickly in spring! For now, you can lightly thin or shorten a few of the tallest stems to maintain a more manageable shape but avoid cutting more than 1/3 of the plant this time of year. If it’s still too tall for your space, plan for a more significant structural pruning next late winter/early spring, before new growth starts. General Tips: Always cut just above a pair of healthy buds or a leaf node. Use clean, sharp pruners to avoid disease. Consider adding mulch and checking soil drainage if plants look stressed or leggy—bigleaf hydrangeas especially like evenly moist (but not soggy) soil.