The life cycle of the garden chafer (Phyllopertha horticola) has the following stages: egg, 3 larval instars, a pupal instar and the adult beetle.
Adult garden chafers (Phyllopertha horticola) have red-brown slightly hairy wings with a dark edge. The neck shield is metallic green to shiny black. In Central Europe, they emerge from the soil in May or June. Low swarming flights just above the soil surface are very characteristic for the garden chafer (Phyllopertha horticola). These flights are carried out by the males, who mate with females that stay close to the ground. Females start to deposit eggs into the soil at a depth up to 5 cm soon after mating. The eggs elongate at laying but in time become nearly spherical through water absorption. Chafer larvae (grubs) have brown heads and whitish bodies, and normally lie in a characteristic 'C-shaped' position. They possess three pairs of legs, of which the middle and hind pairs are approximately the same length. Pupation takes place around March or April. The pupae are cream-coloured to light brown.