Releases are typically of pupae and adult beetles. The larger the numbers released, the better the chance for establishment. A minimum of 2,000 to 3,000 beetles per site are recommended. Releases in successive years will improve the chance for establishment. Beetles may be released at any time after purple loosestrife emerges in the spring until late August.
Beetles released after the summer solstice are likely to feed and overwinter without reproducing.
These same beetles will reappear the following spring to restart the cycle. Place release containers at the base of purple loosestrife plants and allow beetles to emerge naturally onto the foliage. Concentrating beetles on a few plants is recommended. Place 1,000 to 3,000 beetles on or near an individual plant and allow them to redistribute naturally. Releases of adults made during cooler times of the day help to discourage rapid long-distance flights.