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For experimental situations not involving irrigations (cotton/fallow rotation), burial of bolls prior to mid-November permitted greater fall pink bollworm, Pectinophora gossypiella (Saunders), emergence than did placement of bolls on the soil surface. For those same experiments, spring moth emergence from bolls buried in the fall tended to be later and greater than from bolls left on the soil surface. For experiments mimicking cotton/other crops or cotton/cotton rotations, December flooding reduced spring moth emergence to a greater extent than flooding in November or January. Excess irrigation during the winter or no irrigation until midsummer each reduced moth emergence, compared to flooding in early spring. Overall, initial surface placement of infested bolls, then burial in mid-December followed by immediate flooding caused the greatest reduction in spring moth emergence. Availability of soil moisture at the time when photoperiod and temperature were adequate for release of pink bollworm diapause (early April or later) promoted moth emergence. In a dry soil situation, at favorable temperatures, moth captures were dramatically reduced within a day or two after irrigation, remained low for up to three weeks, then sharply increased for a few days. Cultural control recommendations, based on estimates of the pink bollworm overwintering potential, are made for the most common cotton rotation practices used in the desert southwest.