Question
I'm looking for someone able to help me get rid of the brown spots on my birds of paradise tree. My trees have a lots of brown spots on the leaves and the stems. Its kinder sticky to touch and it trips all over the place and onto other plants. What can I do to make it stop and get rid of them. I saw in the mall those trees doesn't have any spots and why do mind gets them as soon as the new leaves fully open.

Answer
Hi Jenifer,

The brown spots are the hard outer shells of scale insects. Scale can be hard to detect. When they are young these sucking insects are slightly oval, slightly raised, translucent bumps about an eighth of an inch long. They can be found along stems and on the undersides of leaves. They don't look like bugs and don't appear to move. As they get older, they develop a hard, dark brown shell. As the infestation increases, these sucking insects will secrete a sticky substance called honeydew that falls onto leaves, furniture and floors. This stickiness is the most obvious sign of scale and the one that most people notice first.

The key to eliminating scale is to treat even the ones that you cannot see. That means thoroughly drenching all leaf and stem surfaces until they are dripping wet. It is also best if you repeat this treatment all over again in 5 to 7 days to catch any crawlers (the translucent young ones) that you missed the first time. After that, you should check your plant weekly to see if they return.

I do not recommend any pesticides because they are all hazardous to use and not 100% effective against scale. The best non-toxic treatment for mealybug and scale is called Brand X Foliage Cleaner. It is available through Southwest Plantscape Products in California (www.southwestplantscape.com). Their phone is 1-800-333-7977. It is a silicon-based product so it is very slippery. Its ability to penetrate is probably the key to its effectiveness because it gets into the tiny crevices that other sprays miss. Because the scales get into the furled leaves before they unfold, I recommend Brand X for treating scale on Birds of Paradise.

You may also prefer to try spraying with rubbing alcohol that will help break through the hard outer barrier of the scale and kill it. Mix 1 part alcohol with 5 parts of water. Add a little liquid soap to help it spread.

Finally, neem oil works similarly to horticultural oil. It should be diluted with water and Pine Sol to counteract the onion-like odor. All of these are available nationwide at plant and garden centers and also by mail order.

Important: None of these should be applied to plants in direct sun or in high temps.

Please let me know if any of this is unclear or if you have any additional questions.

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Regards,
Will Creed, Interior Landscaper
Horticultural Help, NYC

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