How long do praying mantis eggs need to hatch?
Praying mantis eggs hatch after three to six months. In the fall, eggs are laid in a 1-inch-long cluster. The eggs hatch in the spring or early summer, after several weeks of warm weather. Praying mantis babies (nymphs) either all hatch at the same time, or over several weeks in groups.Source:Amateur Entomologists’ Society: Praying Mantid caresheetColorado State University: The Praying MantisThe Ohio State University: Praying MantisMore Information:University of Illinois: I Found a Praying Mantis/Mantis Egg Sac.