Coreopsis Frost Resistance

The frost resistance of Coreopsis varies by species: annual forms, such as Coreopsis tinctoria, do not possess frost resistance. Perennial species demonstrate tolerance across a wide range: Coreopsis grandiflora withstands down to –17–23 °C, while the most winter-hardy species, Coreopsis tripteris, tolerates temperature drops to –34 °C, which corresponds to USDA frost resistance zone 4.

A key survival factor is the condition of the root system, as plant death often occurs not due to low temperatures, but due to winter waterlogging and crown rot in heavy soils. Frost resistance also depends on agrotechnics: untimely pruning after flowering reduces resilience, while maintaining optimal soil water balance before the onset of frost prevents physiological tissue desiccation.