Answer: Sucking insects such as aphids, thrips and white flies can damage iris and spread diseases. Control these pests by spraying a pesticide such as Isotox or Malathion. Check the registration of which chemical you use, and follow the manufacture?s recommendation for rate and timing of application. Insecticide soaps are effective control of most pests, while not harming beneficial insects. Bacillus thurgingiensis (b.t.) is an environmentally safe and effective control for chewing insects such as caterpillars.
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