Preforming floral primordia converge on a narrow range of stages at dormancy despite multiple effects of temperature on development.

Phenological studies often focus on relationships between flowering date and temperature or other environmental variables. Yet in species that preform flowers, anthesis is one stage of a lengthy developmental process, and effects of temperature on flower development in the year(s) before flowering are largely unknown. We investigated the effects of temperature during preformation on flower development in Vaccinium vitis-idaea.