Troubleshooting
Sweet Mock Orange problems — and how to fix them
Sweet Mock Orange (Philadelphus coronarius) 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.
Aphids
Clusters on soft shoot tips in spring; knock off with a strong water jet or treat with insecticidal soap.
Powdery mildew
White powder on foliage in hot, dry summers; improve air circulation by thinning congested stems after flowering.
Poor flowering
Usually caused by pruning at the wrong time — always prune immediately after flowering ends, as next year's flower buds develop in summer.
Leggy growth
Remove one third of the oldest stems at the base each year after flowering to maintain a compact, floriferous habit.
Prevent sweet mock orange problems before they start
Most sweet mock orange issues are care-mismatch, not bad luck. Dial in the basics:
Sweet Mock Orange problems — FAQ
Why is my sweet mock orange aphids?
Clusters on soft shoot tips in spring; knock off with a strong water jet or treat with insecticidal soap.
Why is my sweet mock orange powdery mildew?
White powder on foliage in hot, dry summers; improve air circulation by thinning congested stems after flowering.
Why is my sweet mock orange poor flowering?
Usually caused by pruning at the wrong time — always prune immediately after flowering ends, as next year's flower buds develop in summer.
Why is my sweet mock orange leggy growth?
Remove one third of the oldest stems at the base each year after flowering to maintain a compact, floriferous habit.