White flies may only measure 1/16 inch long, but they can overwhelm and kill your prized tomato plant when present in great numbers. The species attracted to your tomatoes (Bemisia argentifolii and Bemisia tabaci) are also attracted to other garden vegetables, like peppers. Defend your yard and eradicate white flies on your tomato plants before they kill your tomatoes and spread throughout your vegetable garden.
Cut off any tomato plant leaves that are heavily infested with white flies, using pruning shears or garden scissors. Such leaves are typically covered in white dust or small white lumps that are the white flies' larvae. Place the pruned foliage into a sealed bag or container and discard it.
Shoot down the tomato plant with a strong blast of water. This dislodges and drowns the adult white flies and can significantly reduce the white fly population if done at every watering.
Release biological controls in the form of lady beetles (Harmonia axyridis and Clitostethus arcuatus), available from some garden stores and nurseries. These beetles prey upon white flies and can be an effective means of all-natural elimination.
Hang yellow sticky traps, available from most garden stores, on your tomato plants or on stakes near the plants. This attracts the adult white flies, who become stuck to the trap and die.
Spray your tomato plant with a standard insecticidal soap containing neem oil if all other methods of control do not sufficiently reduce the white fly population. Mist the spray onto all exposed areas of your tomato plant according to the product's label, as toxicity varies by product.