9 Plants You Should Never Prune in April, According to Gardening Experts

Lilac

Both experts we spoke to agree: Leave lilacs alone in April. "You remove flower buds and reduce the amount of flowers you'll have to enjoy," says master gardener Charlie Nardozzi.

Instead, prune them after they flower in late spring. This will ensure that they have enough time to set buds for next year.

Bigleaf Hydrangeas

You should wait to prune many kinds of hydrangea as well—namely, bigleaf varieties. These bloom on old wood, so their buds will already be in place by early spring.

"April pruning can result in little to no flowers that season," says Tabar Gifford, partnership coordinator and master gardener at American Meadows. "Limit early pruning to removing dead wood, and save shaping for after the plant has bloomed."

Russian Sage

Russian sage may appear dormant in spring, but don't prune it just yet. Its old stems are important and can help protect the plant's crown.

"Cutting it back too early can expose the plant to cold damage," says Gifford. "Once new growth emerges at the base, it can be safely cut back to encourage full, healthy growth."

Oak Trees

Pruning your oak trees in April can put them at risk for oak wilt, according to Nardozzi. This disease spreads via fresh cuts and is oftentimes fatal to the plant. He recommends pruning in late fall or winter instead to mitigate this risk.

Coneflowers

Pollinators are an important resource not just for your garden, but for the overall environment. Some plants, like coneflower, are cozy homes for these and other beneficial insects; by pruning in April, you may be removing them from your garden.

Nardozzi recommends waiting until later in spring to clean up these perennials.

Beardtongue

These plants shouldn't be pruned heavily in April, especially xeric varieties like Red Rocks.

"Their old stems help insulate the crown through seasonal fluctuations, and removing them too early can lead to stress or moisture issues," says Gifford.

She recommends waiting to prune until late spring when new growth is well established.

Maple Tree

Certain trees, like maple, birch, or walnut, shouldn't be pruned in April. "These high sap trees will bleed excessively, potentially leading to disease," says Nardozzi.

He recommends pruning them in winter or mid-summer instead.

Azaleas

Azaleas set their flower buds during the previous year, so they're best left alone in April.

"Early pruning can remove or damage those blooms before they even open," says Gifford. "It can also expose tender new growth to fluctuating spring temperatures." Wait until after they've flowered to start cutting back.

Switchgrass

Depending on your region, April may be too late to cut back switchgrass.

"New growth may already be emerging, and cutting back old foliage risks damaging those fresh shoots," says Gifford. "Ideally, grasses should be trimmed in late winter to very early spring, just before new growth begins."