Answer: I suggest you get some good reference books, and begin learning about what you will encounter. Pest management will be an important part of your business, and for both environmental and economic reasons you'll want to choose the right pesticides.
Two good reference books to start with are: Greenhouse Gardener's Companion, by Shane Smith (Fulcrum, 1993) and Greenhouse Gardening, by Miranda Smith (Rodale, 1985).
The best approach when tackling any pest management problem is to first identify the pest, determine it's population and/or the extent and type of damage it can cause, and evaluate your options, including cultural controls, biological controls, and pesticides. For example, whiteflies are a big problem in greenhouses; you can purchase a tiny parasitic wasp called Encarsia formosa that will control them. Ladybug larvae eat aphids, another common pest. If, however, you spray a broad spectrum insecticide to kill everything, you may be wasting money and would kill off these beneficials. A good source of all sorts of pest management supplies is the mail-order company Garden's Alive, ph# 812-537-8650.
These greenhouse books should get you started. I hope this helps.
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