5 Plants You Should NEVER Prune In The Summer (And 5 You Should)
If you’re like me, summer is probably when you spend the most time in your garden. Everything’s growing like mad, and it’s tempting to reach for those clippers and tidy things up with a little pruning. But not all plants appreciate a mid-summer trim. Some get stressed, bloom less, or become vulnerable to pests and disease. Others actually benefit from a summer cut and will bounce back better than ever. The trick is knowing which is which. So let’s take a walk through the garden and talk about five plants that you should let grow in the summer, and five that can handle a little pruning.
No Pruning: Lilacs
Lilacs are a staple of spring, but if you prune them in summer, you're basically canceling next year’s flower show. Lilac trees set their buds shortly after blooming, so summer pruning means you're snipping off the very thing you're hoping to see. If you must prune, do it right after the blooms fade, not weeks later. I've made the mistake once, and trust me, a lilac bush full of just leaves the following year is kind of heartbreaking.
Yes Pruning: Lavender
Now here’s one that actually likes a little summer trim. Right after the first bloom fades, a light prune encourages a fresh flush and keeps the lavender plant from getting woody and scraggly. Don’t cut into old wood, though, as it won’t bounce back. Just cut off the spent blooms and a bit of green growth. I do this every July to help the plants stay compact, tidy, and smelling good well into fall.
No Pruning: Oak Trees
Pruning oaks in the summer can actually hurt more than help. In many cases, it invites oak wilt, a nasty fungal disease that’s spread by beetles who love fresh cuts on trees. Oaks are best left alone until winter, when those beetles aren’t around. I know summer feels like a great time to clean up low branches, but hold your horses. The tree will thank you, and you’ll avoid a mistake that’s very expensive to fix.
Yes Pruning: Yarrow
Yarrow usually looks like it’s fading after its first flush, but don’t give up on it. Prune it back by about a third and you’ll usually get a second round of flowers. It responds well to summer pruning, which also helps keep it from getting floppy or leggy. Plus, pruning helps improve cleaner air circulation, which reduces powdery mildew. Think of it as a mini reset button for the plant.
No Pruning: Rhododendrons
These beauties are picky about when they should be pruned. Like lilacs, they form next year’s flower buds shortly after blooming, so if you snip them in summer, you're not just reshaping. You’re actually erasing the blooms! They don’t recover fast either, so pruning late can throw rhododendrons off for a couple of seasons. If yours is looking wild, enjoy its messiness for now and plan to prune just after it blooms next spring.
Yes Pruning: Bee Balm
Bee balm can quickly start to look wild, especially when it starts to mildew. The good news is that it doesn’t mind being cut back in summer. Trim faded flowers and remove scruffy stems, and it’ll often reward you with more blooms and healthier growth throughout the warmer months. I usually thin mine out in midsummer, and the hummingbirds don’t seem to mind one bit.
No Pruning: Spring-Flowering Clematis
It’s easy to forget, but not all clematis varieties follow the same rules. The ones that bloom in spring (like Clematis montana) already have their flower buds set by the time summer rolls around. Cutting them back in summer takes away their ability to bloom again. Like rhododendrons, they don’t recover fast, and you might be staring at a green, flowerless vine next season. So save your pruning for right after they bloom.
Yes Pruning: Catmint
Catmint is a tough little perennial, and it really thrives if you prune it midseason. Once the first bloom is spent, I give it a good shear, about down to half its size. Catmint rebounds quickly with fresh, great-smelling blooms and a second round of flowers. It keeps the plant from getting too long and heavy and keeps the bees happy too. It’s an easygoing plant, especially when it comes to pruning.
No Pruning (Sometimes): Fruit Trees
Peaches, plums, and apples are all tempting targets for a summer clean-up. And yes, there are some reasons to prune in summer, like removing suckers or damaged limbs. But aggressive pruning in heat can stress the tree, slow fruit ripening, or expose the bark to sunburn. I’ve found that approaching fruit trees with a light touch goes a long way. Unless you really know what you’re doing, wait until winter dormancy to make any bigger cuts.
Yes Pruning: Daylilies
Summer is a great time to deadhead daylilies and even dig and divide them if they’re starting to get overcrowded. While they don’t need a hard prune, a bit of summer grooming helps the plant focus energy on flowering and keeps it from looking like a mess. I like to snip spent stems and tidy the leaves. If you’ve got an old clump that’s barely blooming, lifting and dividing in summer can work wonders to revive it.
Pruning With Patience
It’s funny how knowing just a little bit about timing can completely change the way your garden grows. I’ve learned the hard way that sometimes, the best thing you can do is step back and let a plant be. And other times, a small, thoughtful snip can make all the difference. So before you grab your pruning shears, take a moment to do a little research. A quick search could save you tons of work, and even next year’s garden