How do you deadhead and trim rhododendrons and azaleas?

To deadhead rhododendrons and azaleas, remove spent flower trusses with scissors. To trim the plants, snip their branches or remove new buds, and cut back over-sized plants in the appropriate season.

1. Position the scissors

   Place the opened blades of the scissors at the base of the spent flower truss, or dead blossom. Make sure the scissors are positioned above the whorl of leaves.

2. Cut the spent flower trusses

   Snip the stem to remove the spent flower truss. Either collect the dead blossom or leave it as compost.

3. Choose the time for light pruning

   For both rhododendrons and azaleas, wait until after they bloom in early summer. Watch for the spent flowers to start discoloring.

4. Snip rhododendron branches

   To encourage a bushier plant, use your fingers to pinch out single growth buds. Wait until they start to swell. If branches start looking leggy and sparse, use garden shears to snip them back.

5. Remove stray azalea shoots

   Use loppers to reach into the center of the azalea bush and remove stray shoots. Cut next to large, woody branches.

6. Prune over-sized rhododendrons in late winter

   Cut over-sized rhododendron plants back nearly to the stump February or March. Leave a few green shoots.

7. Prune over-sized azaleas in mid-summer

   Cut over-sized azalea plants back to the desired size in mid-summer, keeping as many blooms as possible. Use a slow-release, water-soluble fertilizer to feed plants as they grow. Water frequently to flush suckers from the stump.