The following information pertains primarily to millipedes, since these pests are more commonly encountered. In spring and again in fall, eggs are laid in clusters of 20 to 100 in the soil. Some females deposit as many as 300 eggs. Larvae emerge 9 days to 3 weeks later. Feeding on decaying vegetable matter, larvae grow slowly, developing through about seven instars in 21 to 25 weeks.
Adults are relatively long-lived.
Millipedes overwinter in the soil or in other moist, secluded places. The destruction of favorable feeding and breeding sites is the most reliable method of millipede control. Thatch should be removed from turf for millipede control and other reasons. Compost piles, mulches, and low-growing vegetation should be located away from buildings to retard the entrance of these pests. Foundation walls should be repaired and cracks around doors, basement windows and similar openings should be sealed.