Pocket Botanist
Check these first
- Rub the white spots to see if they wipe off like dust.
- Check if the plant is crowded by other shrubs.
- Look for yellow halos around dark spots.
Likely causes
Powdery mildew
Most likelyHow to tell: You will see a white or gray dusty substance on the surface of the leaves. It may cause leaves to look distorted or eventually turn yellow and drop.
What to do: Improve air circulation by thinning out crowded branches. Spray the foliage with a mixture of 1 tablespoon of baking soda in 1 gallon of water every 7 to 10 days.
Leaf spot fungus
PossibleHow to tell: These appear as distinct brown or black spots with yellow halos. They often occur after long periods of wet, rainy weather.
What to do: Remove and destroy all fallen leaves around the base of the plant to prevent spores from spreading. Avoid overhead watering to keep the foliage dry.
When to worry
Powdery mildew is mostly an aesthetic issue late in the season. If it appears early in spring and covers the whole plant, it may stunt growth.
Stopping it coming back
Plant your viburnum in a spot with good air movement. Water at the base of the plant rather than spraying the leaves directly.
Not sure which one it is? Photograph your mapleleaf viburnum.
This page lists the usual causes. Pocket Botanist looks at your actual leaf and tells you the likely cause, how serious it is, and what to try first. Identification and a health check are free.
Questions people ask
- Should I cut off the infected leaves?
- Yes, removing heavily infected leaves can help reduce the amount of fungus on the plant. Dispose of them in the trash, not your compost pile.
- Will this kill my shrub?
- Rarely. It is an annoying cosmetic problem that rarely kills a mature, established Mapleleaf viburnum.
More problems with Mapleleaf viburnum
Back to the Mapleleaf viburnum guide
This article was generated with AI from the plant’s care profile and is general information, not horticultural advice. Read about how we build these guides.