Q: I believe we have two pineapple guavas by our front door and one is losing its leaves dramatically. There is a “beige colored” hard cocoon about 1.5“on a branch. Also, this bush was bothered by the large multicolored grasshoppers this summer and I suspect they did some damage. Any help you can offer would be appreciated. We are transplants to Florida and trying to learn all about your flora and fauna!!!
A: Welcome to Florida and Nassau County. The leaves dropping may be an indication of root problems. Tell me about your irrigation and fertilization of these plants and how close are they to the foundation of the house.
The cocoon is probably a chrysalis which is the stage between the caterpillar and the butterfly (moths form cocoons which are generally soft, silken sacks). But the cocoon of the guava fruit moth is brownish, beige so I am not sure what insect you have on your shrub. You can use Bacillus thuringiensis Bt), which can be purchased at any garden center. Be careful where you apply it as it kills both moth and butterfly larvae and of course we want to preserve the butterflies.
Grasshoppers are much more difficult to control and many of us have been battling with these pests this year. Using the grab and smash (G&S) method (my personal favorite) may prove the best way procedure. This method entails picking them off the plant and crushing them under your foot or you can take two bricks and grind them right on the shrub. If that seems too gruesome, then you might consider using growth regulators which work best when applied to the grasshoppers when they are small – about 1 inch long. Unfortunately, we often don’t notice them until they are quite large – if that proves true use the G&S method.
Regarding specific information on guava check out the UF publication on guava: http://edis.ifas.ufl.edu/mg045 and insect control on guava: http://edis.ifas.ufl.edu/pi055