Pimples on leaves - Orchid Board

justatypn · #1 06-23-2006, 04:58 PM

One of my keiki's have pimples on the leaves. I have inspected the leaves and see no pests, fungus of any kind, no leaf discoloration either. I did take a partial of the leaf and scraped it a bit to see if they were pustuals, not that either. The parent plant Catt. Christina Princess is not showing any signs on its new growth as well as the other 3 keiki's I got from her. Any ideas ???

Orchid Kitty · #2 06-25-2006, 04:21 PM

I had the same symptom on some plants in the Cattleya alliance. The pimples, or "dots," were round, hard, and smaller than a pinhead. They did not rub off or scrub off. In fact, they seemed embedded in the leaf. I was told that it was a form of hard scale. I sprayed the leaves with Enstar II. After a day or so, the dots got brown and sort of dissolved or died, leaving pits in the leaves. My problem might not be the same as yours, but I'll bet it is a pest problem.

justatypn · #3 06-25-2006, 07:07 PM

I am open for any suggestions at this point. If the problem is not the same Enstar II will not harm the plant and if it is the problem hopefully new growth will be minus the tiny bumps and the microscopic culprit. Within a few days I will be able to tell. Tks for the heads up...

Oscarman · #4 06-26-2006, 12:11 AM

Cheryl, do you have a picture of this affliction. Never heard of this before, it would be interesting to see.

justatypn · #5 06-26-2006, 10:34 AM

I tried to take pictures but with it being of the same color, merely bumpies, its hard to get it in focus. I will try with different light angles, photographer I am not.

justatypn · #6 06-26-2006, 12:22 PM

I tried to get a good photo of the bumpies. Of course, the digital didn't come out showing the problem. I read online about an alcohol rub, but did not want to do this as I was unable to get the correct formula, so I had Schultz pesticide on hand and used this and will see the results in a day or two and if the problem is not resolved than I will pull out the heavy artillary

. I did notice it is also on the new growth just sprouting.

Ironwood · #7 09-28-2006, 07:24 PM

This may be Oedema which is a physiological disorder which causes water blisters when the roots take up more water than the leaves loose through evapotranspiration. In time the blisters will heal over as cork like covered bumps. It is more of a cosmetic problem than harmful and is somewhat seasonal, more likely to occur in spring and fall.

Sandra Billeter · #8 10-05-2006, 02:32 PM

We use a 50% rubbing alcohol spray as a general insecticide for scale, mealybugs, etc. It doesn't harm the plants or blooms but it seems to work well as an immediate solution. You also need to use a pot drench to get complete eradication and the alcohol doesn't work for that.

Sandra in South Carolina