Photo by Melody
It's time now to VOTE in our 14th annual photo contest! Voting ends November 7, so be sure to cast your votes for your favorites in each category here. Good luck to all contestants!

Definition of blackspot

Categorized under "Roses"

Definition as written by paulgrow:

A general term for bacterial or fungal diseases of plants characterized by black spots or blotches especially on the leaves

Definition as written by Joan:

Black spot is one of the most common diseases of roses. It is caused by the fungus Diplocarpon rosae. Black spot will cause a weakening of the plant so that fewer and fewer blooms are formed if the disease is left unchecked. Plants are weakened and increasingly subject to winter injury.

Infected leaves show black spots. The spots can be up to 1/2" in diameter and typically have fringed borders. Yellowing of the leaf begins surrounding the spots and the entire leaf may yellow and eventually drop off. Close inspection of the spots will reveal the presence of tiny black spore producing bodies. The fungus may also infect the canes where lesions appear purple at first and later black.
Rake and discard all fallen leaves because they are the main source of spores in the spring. Prune and discard any obviously infected canes. Avoid wetting the foliage especially during dark cloudy days. Grow plants in an open sunny location to promote rapid drying of the foliage.

Thumbnail of blackspot by Joan
(Click for full-size)


Add a definition to this term

Return to the Gardenology homepage

Return to Dave's Garden


We recommend Firefox
Overwhelmed? There's a lot to see here. Try starting at our homepage.

[ Home | About | Advertise | Media Kit | Mission | Featured Companies | Submit an Article | Terms of Use | Tour | Rules | Privacy Policy | Contact Us ]

Back to the top

Copyright © 2000-2014 Dave's Garden, an Internet Brands company. All Rights Reserved.
 

Hope for America