Whiteflies are minute plant-feeding insects that resemble tiny moths. The wings of whiteflies are often covered with a white dust or waxy powder. They are completely white and can be seen flying off your plants, when you shake them. These insects pierce the outer layer of your plants and extract the liquids contained inside. The whitefly can carry diseases and exude a sticky, sugary concentrate of plant juices that can promote mold growth. It also reproduces rapidly and can become a problem in no time. There are two ways to treat an infestation: pesticides and using other insect predators

Pesticides
The first way to rid yourself of whiteflies is through the use of pesticidic sprays. They are easily eradicated with natural sprays. Most gardening and garden supply stores carry these sprays. The most effective sprays are the ones which contain pyrethrum (Biothrin), although you can also purchase an insecticidal soap or make a homemade spray. These sprays are all usually applied in the same way. First you remove all the leaves that are more than 50% damaged and burn them or cure them in a heated temperature of more than 95 degrees celsius or 200 degrees fahrenheit(to kill all the remaining whitefly eggs). Then spray a fine mist over the infected plants, twice, completely covering them each time. Repeat this treatment about every 5-10 days, depending on your level of infestation. Your infestation levels should improve and begin to show signs of improvement immediately(within a day or two after every spraying). After spraying it would also be wise to add a few natural predators to keep from using harsh insecticides on your plants.

Natural Predators
Natural predators are an excellent way to rid yourself of whiteflies and the damaging effects they can have on your plants. Encarsia formosa are by far the most effective whitefly predator(the only other real alternative is the preying mantis). These small wasps attack whiteflies, they do not sting people. They are so small, once you release them you will probably never see them again. As with all predator insects you must completely wash off all the toxic residues left on your plants from insecticides before you introduce them into your garden environment. The parasite attaches itself to the body of the whitefly and begins to feed on its host and when finished lays its eggs inside its body cavity. The wasps take a couple of weeks to begin showing any affects. You should first use an insecticidal spray to bring down the population and then use the wasps to control the infestation from there on out. After cleaning the toxins from your garden, set the parasites out at 2-3 per plant and repeat every 2-4 weeks throughout the plants life.

Another Alternative
Whiteflies are known to be attracted to the color yellow. If you take some yellow strips of paper and apply an adhesive to it, you can position these around your garden or on the tops of your plants containers as makeshift "whitefly traps". If these strips and just a few encarsia formosa are added at the beginning of your garden whitefly and a few other types of insercts will always be kept in constant check. Good luck with your whitefly problems and happy gardening!