In many plant species and in many accessions of the plant model species Arabidopsis thaliana (Arabidopsis), the well-studied vernalization pathway prevents premature flowering before the long cold periods of the winter (Song et al., 2012). In Arabidopsis, flowering of winter-annual accessions without vernalization is strongly delayed by the MADS-box transcription factor FLOWERING LOCUS C (FLC) (Song et al., 2012; Michaels and Amasino, 1999, 2001; Johanson et al., 2000). FLC forms a repressor complex through interactions with the MADS-box transcription factor SVP (SHORT VEGETATIVE PHASE) to repress the transcription of the flowering promoting genes FLOWERING LOCUS T (FT) and SUPPRESSOR OF OVEREXPRESSION OF CO1 (SOC1) (Li et al., 2008; Lee et al., 2007). As a result of the prolonged exposure to cold temperatures during winter, FLC abundance is gradually reduced, predominantly through epigenetic mechanisms, and flowering repression is gradually relieved (Song et al., 2012). Substantial natural variation in the vernalization-dependent expression of FLC has already been described and characterized in many Arabidopsis accessions (Coustham et al., 2012; Li et al., 2014).