Pruning shrubs helps them stay healthy and vibrant. Pruning is often necessary to help manage the size and shape of shrubs. Also, pruning stimulates the growth of new foliage or flowers, and contributes to an overall, neatly maintained look in the landscape.

Different shrubs have different pruning needs. Some shrubs (like boxwoods) need infrequent pruning, except to remove dead or damaged branches. Most flowering shrubs benefit from deadheading of flowers and light shaping. Roses and hydrangeas have specific pruning requirements, depending on the variety, and timing is often a key factor.

Weather conditions also affect the timing of shrub pruning. Long stretches of hot or dry weather in summer can cause stress to plants, including shrubs. We spoke with some garden experts about pruning shrubs in dry weather, and got some helpful pruning tips.

Should You Prune Bushes When It’s Dry?

Generally speaking, garden experts recommend avoiding heavy pruning in very hot summer weather. But dry weather pruning may have its benefits. Mary Jane Duford, an expert gardener at Home for the Harvest, says that pruning on dry days means there is less risk of fungal disease, since fresh cuts will not remain damp and prone to fungus.

Rhonda Kaiser, a gardening expert who lives in Texas (where summers often get very hot), says the timing and approach to pruning should be tailored to the kinds of shrubs you’re working with, but that heavy pruning in summer may be risky. She says that tender new growth may be exposed and prone to sunscald, due to brighter sun rays and hotter temperatures in summer. She also points out that pruning stimulates growth, and new foliage emerging in hot weather can wilt or burn quickly.

Kaiser suggests only doing light pruning tasks when the weather is dry: this includes tidying up broken stems or light reshaping. But since the weather doesn’t always cooperate with a gardener’s work plan, there are some tips to follow to lessen stress or damage to your shrubs.

Want more gardening tips? Sign up for our free gardening newsletter for our best-growing tips, troubleshooting hacks, and more!

How to Prune Bushes

In addition to using the right tools for the job, and making sure tools are clean and sharp, there are some specific weather-related tips for pruning your shrubs to be aware of.

1. Follow Appropriate Seasonal Timing: To keep shrubs healthy, prune them in the proper season. Some spring-flowering shrubs, like lilacs, should be pruned soon after their flowers fade and before next year’s buds start forming. Many shrubs perform best if pruned in early spring or autumn, while some robust growers, like forsythia, can be pruned almost any time. Kaiser’s rule of thumb is to save heavy pruning for late winter or early spring, while plants are still dormant, just before new growth begins.
2. Prune in Morning or Early Evening: In addition to seasonal timing, the time of day should be considered. Just as watering should be done in the morning or at dusk to maximize moisture retention, pruning tasks should also be done at these times when temperatures tend to be lower, says Kaiser, to help reduce stress on your plants.
3. Water Before and After Pruning: Both Duford and Kaiser recommend watering shrubs before and after pruning. Kaisers says this will support their recovery from the stress of pruning. Duford recommends a deep soak around the root zone the day before pruning, to prepare the plant and offset the stress of pruning. After pruning, Duford says to keep soil evenly moist (but not soggy) to help the shrub recover slowly. She also suggests putting a layer of organic mulch at the base to help conserve water and protect roots.

Tips for Pruning Bushes in the Summer

Sometimes summer brings delightful weather, but there can also be extremes that can take their toll on your garden’s plants. Duford says that dry soil and hot sun can stress plants, so it’s important to minimize additional strain by taking care not to prune too heavily.

She says a good guideline is to not remove more than one-third of the plant’s volume at a time, to lessen stress. It’s also a good idea to wait until after a good stretch of rainy days before pruning, if at all possible.

Additionally, Duford suggests doing mainly light pruning work in summer, including shaping or thinning (removing criss-crossing or overlapping branches to improve air flow and sun exposure), rather than pruning to reduce size. She also recommends removing suckers and water sprouts at this time: new growth that can sap a lot of energy from shrubs.

Pruning your butterfly bushes is one of those necessary, but easily forgotten chores. A fear of doing it incorrectly, plus the busy nature of life, is a formula for an overgrown butterfly bush that doesn’t bloom well.

The good news is that if it’s too late to cut back your butterfly bush this year, there’s a very good chance it isn’t too far gone. Here’s the best plan of action that will ensure your butterfly bush produces an abundance of blooms next summer and fall.

Why Missing the Pruning Window Matters

The best time of year to do a hard prune is in the early spring, but after the final frost. When you cut back your butterfly bushes, you temporarily expose their hollow stems. The stems will take in water, which isn’t a problem if the temperatures stay above freezing. But if water freezes inside the stems, they will likely split.

Additionally, pruning in the spring is best because blooms form on new growth. You’ll be able to spot the new growth on your butterfly bush by the new leaf buds.

Want more gardening tips? Sign up for our free gardening newsletter for our best growing tips, troubleshooting hacks, and more!

3 Steps to Take If You Missed the Pruning Window

If you’ve missed the window for hard pruning in the spring, here’s what to do:

• Deadhead spent blooms: As your butterfly bush blooms throughout summer and fall, remove the spent blooms to encourage more blooming and prevent the seeds from spreading.
• Do a light prune before the chance of a frost: While it’s best to avoid pruning your butterfly bush outside of spring, you can lightly trim a few inches off its stems if it’s invading your other plants. Never prune your butterfly bush if there is a chance of a frost within 48 hours.
• Wait it out: Resist the urge to do a hard prune before next spring. You can do more harm than good if you prune at the incorrect time.

3 Signs Your Butterfly Bush Can Bounce Back

If you’ve missed the ideal pruning window for your butterfly bush (even for several years in a row), don’t dig it up just yet. Here are some signs that you can revive it come spring:

• There is a lot of new growth at the base: Since blooms form on new growth, it’s a good sign if you notice a lot of new growth coming up near the bush’s roots.
• It’s not leggy: If your butterfly bush is overgrown yet still lush and thick, it’s a good sign that it is receiving the right conditions to grow back compact, but more contained.
• It’s in a spot that receives enough sunlight: If your butterfly bush is in a spot that receives eight hours of bright sun, there’s a good chance it won’t grow back leggy.

How to Prune Correctly Next Spring

As a general rule of thumb, cut back your butterfly bush to be about one foot tall in the spring, but don’t go past the new leaf buds forming. This is called a hard prune.

A hard prune is different than light pruning. A hard prune is more drastic and involves cutting back the bush as close to the base as possible. Light pruning (removing just a few inches of the stems) is okay in the early fall, and can actually prevent your butterfly bush from seeding and spreading too much.