Antoine Perrier has just published a new paper entitled "Shifts in vernalization and phenology at the rear edge hold insight into the adaptation of temperate plants to future milder winters" in New Phytologist. You may find the paper here. Here's what he has to say about it:
Vernalization, the exposure to cold temperatures in winter, often regulates flowering in temperate plants. This cue may become unreliable under future milder winters. To get insight into how temperate plants may respond and adapt to future climates, we explored variation in flowering regulation at the rear edge of the plant Campanula americana. Rear edge populations are relicts that persisted under past warming and now occur at warmer range limits, providing ideal models to study evolution under warming climates. Using a combination of citizen science data, greenhouse and field experiments, we found that rear-edge populations of this species adapted to milder winters by relying less on vernalization, instead showing an environmentally-insensitive delay in flowering. This suggests that future milder winters may be less detrimental to rear-edge populations of temperate plant species than populations that occur in colder environments and rely on vernalization to regulate flowering.