Roses mottled leaves
There are 3 common causes, and they need completely different responses — so working out which one you have matters more than treating quickly.
2 of them can kill the plant. Rule those out first.
Check these two things first
- Push a finger into the soil, two knuckles deep. Wet soil plus a wilting plant means too much water, not too little — and it is the commonest reason a plant is dying. Dry soil plus crisp leaves means the opposite. The leaves look nearly identical either way, so the soil is what tells you.
- Turn a damaged leaf over. Half of all diagnoses live on the underside: fuzz means downy mildew, fine webbing means spider mites, clusters of insects mean aphids. Nothing on the top of a leaf is as informative.
Most garden problems are cosmetic and resolve without treatment. Reach for a spray last, not first.
The 3 causes, and how to tell them apart
1.Herbicide Damage
Act nowGrowing conditions
New growth twisted, cupped, fern-like or strap-shaped, with stems that may spiral. Leaves take on a leathery texture and abnormally prominent parallel veins. Older leaves below stay entirely normal.
How to know it is this one
Only new growth is affected; older leaves are untouched.
2.Spider Mites
Act nowPest
Fine pale stippling across the leaf, as though it had been sprayed with a very fine dust of pinpricks. Leaves go bronze or grey, and fine webbing appears between leaves and along stems in bad infestations. The mites themselves are just visible as moving specks.
How to know it is this one
Fine even stippling rather than discrete spots or holes.
3.Thrips
TreatablePest
Silvery or bronze streaking on leaves and petals, speckled with minute black dots of excrement. Flowers open distorted or streaked. The insects themselves are slender slivers under a millimetre long that dart when disturbed.
How to know it is this one
Silvery or bronze streaks, not spots or holes.
Still not sure?
The diagnostic key adds two more questions — which part is affected and where the trouble started — and those usually settle it.
Run the diagnostic key