Flowering is a key component of plant adaptation, affecting geographical distribution and suitability for farming practices. It is highly relevant to yield, quality and environmental considerations as flowering at the appropriate time ensures best use of the available growing season, promoting sustainability and reducing the need for inputs. The genus Brassica includes species with many morphological forms that are cultivated for use as vegetables, oils, fodder and condiments, and much of this morphological diversity can be attributed to variation in flowering time. Biennial cultivars require a period of cold treatment (vernalization) to induce flowering. This flowering behaviour is critical for the production of some vegetable forms and for adaptation to certain agricultural practices, such as planting of overwintering cauliflower varieties. Annual Brassica cultivars do not require cold treatment to flower, although some annuals can respond to vernalization by flowering earlier and more uniformly. How different varieties respond to vernalization has a big effect on when and how they mature. Many vegetables are harvested and eaten at the vegetative stage, prior to flowering. Successfully predicting the timing and length of the vegetative phase has a big influence on the quality and commercial return from the crop. For other vegetables it is the timing of the floral transition that is critical. In this project we will identify genes which can exert greater or lesser control on the vernalization process with the aim of using this information to produce parent lines and hybrids which have a more predictable harvest period. We will relate variation at these loci to performance under present and historical weather patterns to associate specific allelic combinations with maturity under different climatic conditions. Knowledge of key Brassica vernalization genes and how they vary in different vegetable Brassicas will allow us to address key questions about the impact of climate patterns on the availability of UK-produced quality Brassica vegetables.