Rhododendrons are acidic-loving shrubs that produce large clusters of showy flowers and grow in U.S. Department of Agriculture plant hardiness zones 4 through 9. These versatile shrubs are generally a welcome sight in most gardens. However, when a rhododendron becomes diseased, damaged or unwanted, killing it may be your only option. Thankfully, you can kill the rhododendron with manual and chemical methods.
1. Manual Control
1 Wait for the spring or fall when the soil is moist to manually remove the shrub. Put on work gloves.
2. Manual Control
2 Remove all stems and branches off the rhododendron with garden loppers, leaving only the main stem. Cut the stem close to ground level, leaving about 2 to 3 inches of stump protruding above the soil.
3. Manual Control
3 Insert the end of a shovel into the ground a few inches out from the rhododendron stump. Dig a small trench around the entire rhododendron stump.
4. Manual Control
4 Insert the shovel at an angle into the soil with the tip of the shovel going under the rhododendron rootball. Push the shovel hand down toward the ground to propel the rootball and the shrub stump out of the soil.
5. Manual Control
5 Dispose of the stump and root ball. Monitor the area for newly emerged sprouts, digging them out of the ground when they appear.
6. Chemical Control
1 Remove all stems and branches off the rhododendron with garden loppers, leaving only the main stem. Cut the stem close to ground level, leaving about 2 to 3 inches of stump protruding above the soil.
7. Chemical Control
2 Pour glyphosate, triclopyr or 2,4-D herbicide in a chemical-resistant, disposable container. Dip a paintbrush into the container, saturating the bristles with the undiluted herbicide.
8. Chemical Control
3 Paint the rhododendron stump with the herbicide immediately. Monitor the stump for new growth, spraying any emerged seedlings with herbicide.
Items you will need
- Work gloves
- Garden loppers
- Glyphosate, triclopyr or 2,4-D herbicide
- Chemical-resistant, disposable container
- Follow the instructions printed on the herbicide label for best results.
- Wear protective clothing -- goggles, rubber gloves, pants and long-sleeve shirt -- when working with herbicides.
- If more than a few minutes have passed since cutting the stump, cut 1/2 inch off the stump before painting it with the herbicide.
- Fine Gardening: Genus Rhododendron (Azalea)
- Arizona Cooperative Extension Backyard Gardener: Killing Whoody Plant Stumps
- City of Seattle Website: Woody Weed Management
- The Ohio State University Extension Fact Sheet: Herbicides Commonly Used for Controlling Undesirable Trees, Shrubs, and Vines in Your Woodland
- UC IPM Online: Woody Weed Invaders
- Jupiterimages/Photos.com/Getty Images