|I sprayed my citrus trees with Hoticultural oil last week to control whiteflies. I see today that there are once again flies around the trees. How soon can I re-spray the trees, and can I do so while they are in bloom?
|Never spray the trees when a large number of adult whiteflies are present. Instead, wait 10 to 12 days until most of the adult whiteflies have disappeared. This will allow enough time for the eggs to hatch and the young to be killed before thay can causemuch damage. Take a look at the leaves and verify that the nymphs are present, and be sure to get good coverage on the undersides of leaves. It may be risky to use a regular grade horticultural oil on your citrus at this time (the label should have extensive information about when you can spray different crops). If you find that the oil you're using can't be sprayed at bloom or during the summer, check out Oil-Away from Gardens Alive. It's a brand new product that's vegetable oil based rather than petroleum based, so is easier on plants and can be applied all seasons. Give them a call at 812/537-8650 for more information about the product, and see if it will work better for you.