The sexes of the marbled white mix freely and there does not appear to be any form of ritualized courtship or territorial behavior. Often females are mated immediately after making their maiden flight.
The female drops her eggs randomly [rather than laying them] among the tall vegetation. As soon as the lime green caterpillar hatches it goes into hibernation. It will start feeding on red fescue in spring when fresh growth occurs. Cocoons are usually at ground level, the adults emerge in the second half of June on warm sunny days.