Greenhouse Ornamental Pests

Melissa Scherr and Lloyd Nackley
Latest revision: 
March 2022

In all cases, follow the instructions on the pesticide label. The PNW Insect Management Handbook has no legal status, whereas the pesticide label is a legal document. Read the product label before making any pesticide applications.

Note: Products are listed in alphabetical order and not in order of preference or superiority of pest control.

Always use appropriate safety equipment when applying pesticides. This is especially important in greenhouses, where the enclosed space presents the special dangers of inhaling materials. Use approved respirator equipment when making these applications.


  1. Materials and methods listed here should not be used for food crops, including vegetable starts.
  2. Not all pesticides listed for a particular pest are registered on all greenhouse crops. Be certain to check the label regarding your application.
  3. This information is presented to assist you in selecting appropriate pest control methods. The pesticide label is the final word on what does or does not constitute a legal application. Due to the wide variety of plants, locations, and conditions under which pesticides are applied, greenhouse plants are particularly susceptible to insecticide injury. Phytotoxic effects that have been observed are noted on the manufacturer’s label. To test for phytotoxicity, treat a small number of plants and observe for plant injury. In general, sprays prepared from wettable powder (WP) formulations are less likely to cause injury than those prepared from emulsifiable concentrates (EC), but wettable powder sprays may leave an undesirable residue on some plants.

A few simple greenhouse sanitation practices can decrease the frequency of insecticide application. Weeds under the benches provide food for greenhouse pests and can be a source of reinfestation. Miscellaneous plants that are not part of a crop, but that are kept for long periods, may contribute to greenhouse pest problems. Such plants may harbor insect pests from one crop to the next. Weed growth outside the greenhouse, particularly against the sides of the building, also can be a source of infestation.