Choose a country to see content specific to your location

Skip to main content

Rose Black Spot

Diplocarpon rosae

Rose Black Spot, Black Spot

by cms-admin. All rights reserved

Black Spot of Rose is the single most common and impactful disease of Roses globally. It is a pretty nasty fungal disease that appears as black spots on the upper surface of rose leaves. Besides looking unsightly in can seriously weaken a rose plant and affect overall vigour.
Free download for your phone or tablet
Download on the App StoreGet it on Google Play


Circular black spots that can reach up to 50mm with a perforated or feathery edge and often with a yellowish halo around the spot. Severe infections will cause the spots to run together and cause a large, black mass.

Growth factors

Infections occur during damp and humid periods because wet conditions are required for the disease to spread.


Leaves turn yellow and drop early.
Plant vigour is greatly reduced.
With times a plant can loose all it's leaves.
Black spots on upper side of leaf occurring from the bottom up of a plant.

Biological treatment

Always remove or destroy infected leaves immediately and try using Neem oil as a biological treatment.

Chemical treatment

Anti-fungal applications like Chronos, which contains a imidazole prochloraz zinc complex can be used to treat black spot. Always read the instructions supplied on the packaging.


The spores germinate and penetrate rose tissue in 9 to 18 hours or longer; new leaf spots appear in 3 to 16 days and spores in 10 to 18 days. The cycle may be repeated throughout the growing season.


First and foremost, give your Rose plant what it needs. A healthy plant is less susceptible to problems and diseases. Ensure good air circulation for your Roses by not planting them close together and pruning often when they become dense. Avoid overhead-watering, especially later in the day and mulch well beneath your plants to reduce water splashing up on leaves. Plant resistant cultivars and last but not least, treat the bush with preventive sulphur spray in spring, before new growth arises. Spores won’t grow on sulphur and you will need to repeat the application after each rain as it will wash off.

Affected plants

A red rose on a Rosa plant


Rosa spp.

Free download for your phone or tablet
Download on the App StoreGet it on Google Play

Plant Knowledge

Search our ever-growing knowledge base to find plants and information. Find out about pests and diseases you should be keeping an eye out for. Watch How to videos or follow step by step guides for tasks in the garden. Free download for your phone or tablet.
Download on the App StoreGet it on Google Play


About usCareersPrivacy policy

Candide is your guide to visiting UK public gardens. Find the best gardens, buy tickets and enter with just your phone. Download the app for offline tickets, community access and more.

Terms & ConditionsCode of Conduct

© 2022 Candide

Made in Bristol