Orchids have few insect pests or diseases if properly cared for. It is important to have a problem identified before attempting control. Take a sample to your county Extension agent and follow recommended treatments suggested. Many disease prevention tips are provided in an orchid disease guide published by the American Orchid Society. Wiping leaves with a warm, soapy, wet cloth is sufficient to eradicate insects like mealy bugs if you have but a few plants in the house. Be careful because many insecticides can damage your orchids. Read the label to see if the pesticide can be safely used on orchids specifically. If you have questions, ask your county Extension agent.