June 05, 2024 ยท Landscape Trimming & Pruning
Trimming at the wrong time usually won't kill a shrub, but it can eliminate an entire season of flowers or leave tender new growth exposed to winter damage. We see both mistakes every year across Hamilton County. Here's a straightforward timing guide for the most common shrubs and hedges in the Noblesville, Carmel, Westfield, and Fishers area.
Spring-Blooming Shrubs: Prune Right After They Flower
Lilac, Forsythia, Azalea, Rhododendron, and most Viburnum varieties bloom on "old wood." That means the flower buds formed the previous growing season on last year's branches. If you prune these in fall or early spring, you're cutting off next year's blooms before they have a chance to open.
When to prune: Within two to three weeks after the flowers fade, usually late May through mid-June in Hamilton County. This gives the plant the rest of the growing season to form new buds on the fresh growth, which will become next spring's flowers.
The most common mistake we see with lilacs specifically is homeowners or landscapers trimming them in October to "clean them up for winter." That removes every bud, and the homeowner wonders why their lilac didn't bloom in May.
Summer-Blooming Shrubs: Prune in Late Winter or Early Spring
Butterfly Bush, Rose of Sharon, Crape Myrtle, and Hydrangea varieties that bloom on new wood (Panicle and Smooth types like Limelight and Annabelle) flower on growth produced in the current season. Pruning in late winter or early spring encourages vigorous new growth that produces more flowers.
When to prune: Late February through March, before new growth starts. You can cut these back hard. They'll push new growth from the base and bloom on that fresh wood in summer.
One exception: Bigleaf and Oakleaf Hydrangeas (the ones with pink or blue mophead flowers) bloom on old wood, like spring bloomers. Prune those after flowering in summer, not in late winter, or you'll lose the blooms.
Evergreen Hedges: Shape in Late Spring and Mid-Summer
Boxwood, Yew, Holly, and Juniper can be shaped once or twice during the growing season. The first trim typically happens in late May or early June after the spring growth flush has hardened off. A second lighter trim in mid to late July keeps things tight and formal through fall.
The critical rule: Don't trim evergreen hedges after mid-August. Late-season pruning triggers new growth that won't have time to harden before the first freeze. Those tender new shoots get killed by frost, leaving brown-tipped branches that won't fill back in until the following spring. We see this every year on properties where someone trimmed their boxwood in September trying to make things look neat for fall.
Ornamental Trees and Large Shrubs
For ornamental trees like Japanese Maple, Dogwood, Redbud, and Crabapple, the best pruning window is late winter (February to early March) while the plant is still dormant. Pruning during dormancy lets you see the branch structure clearly without leaves in the way, and the plant heals pruning cuts faster once spring growth begins.
Avoid pruning oaks between April and August to prevent oak wilt disease transmission. For most other trees, the dormant-season window is the safest and most effective time.
The Simple Rule
If it blooms in spring, prune after flowering. If it blooms in summer, prune in late winter. If it's an evergreen hedge, shape in late spring and midsummer. If it's a tree, prune when dormant. And if you're not sure, just call us.
Our trimming and pruning service follows the right schedule for every plant type on your property. We serve homes and businesses across Noblesville, Carmel, Westfield, Fishers, and surrounding Hamilton County communities. Call (317) 900-7151.