Life cycle of thrips Thrips are a major problem in greenhouse horticulture. They can easily overwinter and attack plants early in the season. The eggs of thrips are kidney-shaped and are laid in leaves, flower petals and in the soft parts of stalks. Before a female deposits an egg, she first makes an opening in the plant tissue. After hatching the larva immediately begins to feed on plant tissue. The first instar larva moults into a second instar larva. This second stage larva is bigger and has