I live near Atlanta, Georgia, and when I noticed my tomato plants had whiteflies, I immediately headed down to our local hardware superstore. I had all intentions of purchasing an insecticidal soap that I had used in the past; however, the shelves were empty with the insecticidal soap. I sought out alternatives to kill the whiteflies and an alternative that was also safe for my fruits.
As luck would have it, an Ortho representative was at the store to help customers. He told me to use Ortho Max Flower, Fruit, and Vegetable Insecticide as a replacement for the insecticidal soap I was looking for (also made by Ortho.) I asked him about whiteflies, etc., and I took note that the label said it did, indeed, kill whiteflies.
Some tidbits about Ortho Max Flower, Fruit, and Vegetable Insecticide:
* The main ingredient is 0.6% Acetamiprid
* It is toxic to wildlife (per the MSDS you can find online)
* It contaminates water
* I highly recommend gloves and eye protection
* Spray average is once every 7 days and no sooner than 7 days before harvesting.
As soon as I returned home, I immediately sprayed my tomato plants with the Ortho Max spray: top of leaves, underside of leaves, stems, around the stem base, etc. I did so after the sun had gotten to the other side of the house as you are not supposed to spray in direct sunlight. Unfortunately, I did not heed my own advice above, and I did not wear gloves (nitrile preferably) nor eye protection. My eyes were fine. My skin was not. The warning on the bottle says to wash skin thoroughly upon contact as the main ingredient can be absorbed through the skin. Within a minute of spraying, my skin became sensitive to touch, numb, and I immediately felt a slight burning. Needless to say, I washed my hands immediately and put on some garden gloves (better than nothing.)
Satisfied with the saturation level, I stopped spraying, and I was confident the whiteflies would die. Alas, I was incorrect.
Within a few days, I noticed the bottom leaves of my plants getting yellow and dying, and I saw an influx of whiteflies in areas I KNOW had received a saturation (if not super-saturation) of insecticide! It was as though the whiteflies were laughing at the insecticide.
I will never buy Ortho Max Flower, Fruit, and Vegetable Insecticide again. Besides the insecticide not doing its job, the spray nozzle provided on the bottles stopped spraying (mechanical issue) when there was 1/3 of the bottle remaining.