I got this from Fairchild Nursery in Miami. They use this method in their mango groves.

1. Stop spraying insecticides; other than occasional neem and soap (I hardly use these anyway)

2. Designate an area for planting wildflowers and use wildflowers as groundcover for your fruit trees. They won't sap much in nutrients and anyway, you're going to use the dead plants for mulch anyway, so it doesn't matter.

3. The wildflowers will naturally reseed themselves and the cover will attract tons of pollinators; fruit set will dramatically increase. I've never had so many bees in my yard.

4. The flower groundcover also provides a nice home for beneficial insects that will do the work that your spraying used to do; without harming the bees. Fairchild reports that they never have to spray now, and I'm finding that I don't either.