Troubleshooting
Garden verbena problems — and how to fix them
Garden verbena (Verbena × hybrida) is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Powdery mildew
Greyish-white coating on foliage in humid or crowded conditions. Improve air circulation, avoid wetting leaves, and apply a sulphur-based or copper fungicide at first sign. Choose mildew-resistant cultivars where possible.
Spider mites
Fine webbing and stippled, bronze foliage indicate infestation, especially in hot, dry conditions. Knock mites off with a strong water jet, then treat with insecticidal soap or neem oil, repeating weekly for 3 cycles.
Legginess and sparse flowering
Caused by insufficient light or failure to deadhead and pinch. Cut stems back by one-third mid-season to rejuvenate growth and restore compact form and flower production.
Prevent garden verbena problems before they start
Most garden verbena issues are care-mismatch, not bad luck. Dial in the basics:
Looking for garden verbena in general rather than its problems? Read the full garden verbena care guide — light, water, soil and feeding.
Garden verbena problems — FAQ
Why is my garden verbena powdery mildew?
Greyish-white coating on foliage in humid or crowded conditions. Improve air circulation, avoid wetting leaves, and apply a sulphur-based or copper fungicide at first sign. Choose mildew-resistant cultivars where possible.
Why is my garden verbena spider mites?
Fine webbing and stippled, bronze foliage indicate infestation, especially in hot, dry conditions. Knock mites off with a strong water jet, then treat with insecticidal soap or neem oil, repeating weekly for 3 cycles.
Why is my garden verbena legginess and sparse flowering?
Caused by insufficient light or failure to deadhead and pinch. Cut stems back by one-third mid-season to rejuvenate growth and restore compact form and flower production.