Wasps only over-winter as Queens, at the beginning of spring they emerge from the place they have spent the winter and find a suitable place to build a nest. She starts by building a small nest of wood paper, which is a mixture of wood and saliva, this nest starts with about 12 hexagonal cells in which she lays an egg in each. She raises these eggs herself until they emerge as workers (Sterile females). Different wasps make nests in different places some in the ground while others prefer hedges.
These workers then take over the maintenance and expansion of the nest whilst the queen effectively becomes an egg factory, the colony then undergoes a rapid growth phase.
The peak of the nest comes in September, when there can be between five and ten thousand workers in a nest. At this time fertile males and females will be laid, as these hatch and mate the females will become next years queens whilst all the workers and males will die off over the weeks to come. During this stage when the workers have no purpose they become more aggressive. Old nests are never.