Paper Reviewed
Sheth, S.N. and Angert, A.L. 2016. Artificial Selection Reveals High Genetic Variation in Phenology at the Trailing Edge of a Species Range. The American Naturalist 187: 182-193.

Noting that "if populations at the edge of a species range have lower genetic variation in phenological traits than central populations," Seth and Angert (2016) state that "their persistence under climate change could be threatened." And to test this hypothesis, as they describe it, they "performed artificial selection experiments using the scarlet monkeyflower (Mimulus cardinalis) and compared genetic variation in flowering time among populations at the latitudinal center, northern edge and southern edge of the species range."

This work revealed, in their words, that "high-latitude populations at the leading edge and latitudinally central populations may be unable to adapt quickly enough to keep up with climate change," but they found that "low-latitude, trailing edge populations have ample genetic variation to rapidly respond to natural selection on flowering time, indicated by a response to selection of ~7 and ~11 days on early and late flowering, respectively, after only two generations of selection," leading them to conclude that "in the presence of strong selection for early flowering, the southern populations in our study may be able to adapt to changing conditions in situ, while individuals from the northern and central populations will likely have to migrate northward to track climatically favorable conditions."

So one way or another, the flowering perennial appears well prepared to cope with whatever degree of warming might possibly come its way.