For some reason, the former owners of my home planted 40 Rhododendrons and 12 azaleas before they sold the house. I don’t know why.

What I do know is that, once I noticed I had so many rhododendrons, I had to learn how to take care of them.

The biggest and hardest lesson was that you need to Prune them regularly or they’ll grow to 60-feet tall. Then, they’re difficult to care for and they often grow together.

Here are my tips:

1. Plan your pruning so you can finish by July 4^th. Prune just after blooming or when buds start to become active. Rhododendrons don’t like to be pruned in hot weather. In my experience, they droop if pruned when it’s hot. Also, buds set in mid- to late-summer, so summer Pruning after July 4^th will decrease next year’s bloom count. Late pruning – late summer into fall – not only cuts bloom count but also produces a spurt of tender foliage that may not have time to harden up before the killing frosts of winter.

2. Remove dead, dying, or diseased branches any time. Cut back flush with the main branch or trunk.

3. Shape your plants and remove branches that are crisscrossing each other. Cut back branches to the next live branch or trunk. If you want to cut off part of a branch, trim to the last set of leaves you want to keep. A topiary shape often works.

4. Cut back your plants if they’re getting too big. I prune mine so that I don’t have to use a ladder to prune them. You can reduce rhododendrons to about a third of their size. However, this and other severe pruning means it will be two or more years before they have flowers. For some rhododendrons, you can cut them off six inches above the ground, and they’ll grow back. That’s what I did to the rhododendron in the photo. I was thinking about planting a fruit tree in that space. But the rhododendron grew back, much to my surprise.

5. Make spaces between your rhododendrons, if you have large ones that are growing together. It helps to be able to walk around them to take care of them.

6. Prune the plants so that they don’t touch the house or fence. They can cause damage or mold to grow due to lack of air flow.

7. Trim off any branches that are dragging on the ground. Insects can crawl from the ground up into the plant more easily. Also, if the rhododendron is by the lawn, there needs to be space for the lawn mower to cut the grass.

8. Deadhead or remove the old, dying blossoms as you prune. Be careful not to remove the emerging new growth under them.

9. Get help with your rhododendrons if they’re causing you stress. I got really lucky and met Deane Rimerman, a forester, who helps me with my pruning. I was standing on the 11^th step of my 12-foot ladder and reaching up to prune my rhododendrons one year. That’s dangerous for an older adult.

Best wishes with your rhododendron pruning. I work on mine every year now. When I didn’t pay attention, they got way too big.

See Washington State University Extension’s “Rhododendrons” for more details on growing these beautiful plants.