05/28/2026
Our local horticulturist, Julie Hill, answers questions from residents. Take a look, and join the next session! See the links in the post attached.
🌱 This Week in the Garden: Your Questions Answered, Week of May 25
The birds are singing, the sun is shining, and we are back to the glorious spring weather Wisconsin has to offer. What’s been happening in your yard and gardens lately?
âť“ Question:
Small caterpillars or worms have completely devoured all of the leaves on one of my bushes (see photo below). What can I do to stop them and should the bush be removed?
🌿 Answer:
Those are the larvae of viburnum leaf beetles (VLB for short). VLB larvae typically appear in early to mid May and can cause significant damage to viburnum shrubs. Then the larvae will move down into the soil to pupate before they emerge as adults in late June - early July. Any treatment methods are targeted towards the larvae and adults.
If your viburnum was a healthy plant, it’s possible that it could recover and isn't totally dead yet. However, if it's been suffering through multiple years of VLB infestation and/or other stressors, then it could be declining and it might be best to replace it.
What are your options?
Keep the shrub, see if it recovers, and treat VLB eggs and larvae as indicated by our fact sheet linked below. If you do keep the shrub, I wouldn't recommend digging up the soil (to try to find the pupae) around it as that can cause more stress or harm to the plant.
Replace the shrub with another viburnum but check out our fact sheet for varieties that are less susceptible to VLB damage.
Replace the shrub with something totally different.
đź”— Learn more:
https://hort.extension.wisc.edu/articles/viburnum-leaf-beetle/
âť“ Question:
What else can I do to support pollinators in my yard?
🌿 Answer:
Pollinators need three core habitat features: Food, Shelter, and Protection - especially from chemical insecticides. A healthy pollinator habitat provides a mix of flowering plant species that bloom at different times throughout the growing season. Therefore, planting native species that support insect pollinators is always a good thing to do! They also need safe places to nest, overwinter and find refuge. This can include stems and branches, leaf litter, bare ground, dead wood, brush piles, and rock piles. Did you know that most of our native bees are solitary bees (meaning they live alone) and 70% of them nest underground? And they need protection from habitat disturbances and chemical pesticides (especially insecticides) which can be directly and indirectly harmful to our insect pollinators. A new study suggests that reduced chemical use is MORE important for conservation efforts than just planting more flowers. Read more about this study in the link below.
Join Julie Hill, your local Horticulture Educator, to learn more about how you can support pollinators in your yard at “Planting for a Buzz: A Guide to Pollinator Friendly Gardening” on Wednesday, June 3rd at 1PM at Barrett Memorial Library in Williams Bay.
đź”— Learn more:
https://grow.cals.wisc.edu/priority-themes/food-systems-priority-theme/what-a-wild-bee-wants
https://www.williamsbay.lib.wi.us/site/events/
đź’¬ Have a question of your own?
Reach out—we may feature it in an upcoming post!
You can reach Julie, your local horticulture educator by calling 262-741-4958, Text 262-374-4191, email [email protected] or use our online form: go.wisc.edu/PlantQ
đź“·Viburnum leaf beetle larvae
