Black Spots on Curry Leaf Plant

October 15, 2011 9:19 AM

Block spots on my curry leaf plant (Murraya koenigii). What's killing my poor plant?

I have a curry leaf plant, which has been growing well for about a year. A while ago, however, we've been noticing these black spots on the back of the leaves. The spots actually seem to be some kind of growth, which can be scraped off the leaves.

Last week the spots became really prevalent, covering almost all of the leaves on the plant. The plant also started to look quite sick.

Does anybody know what those spots are, and how I should save my curry plant?

Photos of the plant and the spots:

Curry plant. The left one is wilting quite badly.

The black spots on the leaves.

Closeup of the spots.

posted by destrius to Home & Garden (3 answers total)

Response by poster: I should also note that we live in Singapore, i.e. a tropical climate.
posted by destrius at 9:53 AM on October 15, 2011

Might be scale? "often mistaken for natural deformities." This site says you can treat it with rubbing alcohol. I tried using a neem oil spray like this one when I had it on my lemon tree ... which died. So, I don't know what kind of success you'll have. Sorry :(
posted by librarina at 11:20 AM on October 15, 2011

I had a very similar infestation (sooty, scaly, could be scraped off) on a camellia bush and successfully treated it with white oil. Whether or not white oil is suitable for curry leaf plants, I'm not sure. You can get white oil ready to use in a spray can, but I use a white oil that needs to be diluted in a sprayer, so perhaps it might be good to start with a weaker dilution?
posted by ninazer0 at 7:46 PM on October 15, 2011