Insects targeted for exclusion may enter the screened environment when outside greenhouse doors are opened. Once the screening is in place, a simple but sizable entry area is best for maintaining easy labor and equipment access to the greenhouse. Once the double-door entry system is installed, add positive airflow to further discourage insects from entering the greenhouse. One simple design places louvers on the greenhouse side of the entryway. When the exterior door to the entryway is open, an exhaust fan is triggered to blow greenhouse air out against this door.
Outside insects are unable to fly against the air stream, thereby excluding entry.
Ensure that the newly screened greenhouse is clean from the start. Before bringing new plants into the greenhouse, remove weeds and plant debris and apply an insecticidal smoke to rid the structure of insects. Carefully examine plant material before introducing it into the greenhouse. If insects are present, rogue infested plants, dip them in an insecticide, or simply remove infested leaves. Monitor the crop regularly for insects by examining leaves and yellow sticky cards.