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I have a bunch of bougainvillea plants out front and something's eating them. I THINK it's mites and have been treating with systemic insecticide (Bayer tree & shrub) - which does help but not for long. I know they are in trouble again when the leaves start to look sickly and then fall off. FINALLY was able to treat when the 40-day rains stopped, but I just wonder whether this is the answer. The label says you only need to treat like once a YEAR and I seem to need to treat once every couple of MONTHS.
The plants are in full sun btw and are up against a rock wall (meaning they get extra heat there, too).
The reason I think it's mites is that there's no sign of any other buggers. They get tiny red or brown dots on the underside of the leaves, then the leaf gets wilty and falls off. Any suggestions?
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Not sure, but are the dots spots, or raised? if spots, it sound more like a fungal disease....also mites are usually very active & will move...do your dots move alot, or are they stationary? stationary may be a gall....& really harder to treat with chemicals..
For a good general bougainvilla site:
http://www.bgi-usa.com/bougainvillea-res...seases.php
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Thanks for the site info, Carey. It was very helpful.
I'm wondering now if I have a little bit of a mite problem PLUS a fungal problem. I do have webbing on the leaves - altho not nearly as dense as that shown on the site there, but definitely webbing. On closer look with a magnifier, I can see the little buggers on there moving around, teeny tiny guys I can't magnify more to see well, sorta gray colored -- so they could be the mites the site shows closeup. I also see little teeny white flying buggers around the plants. Not many, just a few - these fly like white flies, but they are far smaller than any white fly I'm used to from the mainland. They fly up from the grass that's growing in front of the plants and sometimes I see them down in the compost the plants are planted in. All that, plus rust spots as described in the guy's fungus section - that was the red dots I mentioned - definitely light in center and rusty around edges, w/the rust color on some leaves' edges. The brown dots I mentioned are really more like black I think, raised, and fall off if you touch them. There's also little bits of white here and there.
SO - what to use? I also sprayed with insecticidal soap - but it actually seems worse since I did so. It's so frustrating to me bc I've always grown bougainvillea in Calif. with very little maintenance. Thanks again for your help.
None of the photos I've seen online of gall look like what I'm seeing btw.
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What a problem. What about something like a natural predator to mites?? If its flies maybe a wasp can help you out. I sure do hope you find a solution to your problem.
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turns out the guy at rosette's tells me that it was probably too much water from all the rains. He says too much and too little can have same effect. Advice is that if you're getting a lot of rain, pull back your mulch; too little rain, cover the base of the plant. They're looking MUCH better with more balanced rain now. But will continue with the regular systemic insecticide treatment. Thanks, everyone.
Very interesting! Glad you solved the mystery!
Bougainvillea should definitely love the location you have for them. They really do best if they are pretty dry. I see them growing along Queen Ka'ahumanu Hwy north of Kona, and imagine how little they are cared for, but they flourish.
My philosophy with plants is generally that the bugs don't win if the plant is happy in the environment. If the sun/shade and water are right, and the drainage is proper, the breeze not too much or too little, and it has food (if needed), the plant will overcome the bugs and the fungus, at least enough to be healthy, if not picture perfect.
If the environment is wrong, treating for bugs may be ineffective.
There are certain plants here that are huge targets for specific pests, but it may be better not to fight it and grow something else.
The downside of my philosophy is I have lost some plants and had some with munched on leaves and so forth.
The upside is I've gardened manically for about 15 years without really using much of anything in the way of insecticides or fungicides. I don't like handling poisons. I use a hose stream to knock off aphids, scale, mealybugs if they get too bad. (I did spray my roses in California with fungicide.)
