Technical Abstract: A rearing protocol for the predaceous ground beetle, Poecilus chalcites (Say), is described. The effects of dietary constituents, substrate moisture content, and substrate type on larval developmental rates and size were examined in the laboratory. The protocol was successful in obtaining nearly 80% pupation rates, although adult size was smaller than field-collected beetles, and laboratory-produced adults did not lay eggs. We determined experimentally that some of the components of the meridic diet used for colony production could be removed without compromising larval size or developmental rates, but that nutrition beyond cat food was necessary to increase larval size. We found a positive correlation of larval size with increased moisture content using vermiculite substrate at three moisture levels (33.3, 50.0 and 66.7% by weight). Untreated Fer-Til® (GreenGro Products, Jackson, WI) soil resulted in the highest pupation rate (70 to 80%) and had one of the shortest developmental periods of the five soils tested. Steaming or sifting Fer-Til soil compromised its ability to support larval development until pupation.