The genetically determined ability of lily bulbs to withstand unfavorable winter conditions. It is mainly evaluated by the percentage of plant loss after overwintering during several years of testing.
In the reference
91
varieties
crop Lily,
where this is mentioned in the description.
To assess the winter hardiness of lilies, survival statistics of bulbs, scoring within complex economic and biological indicators, and the artificial freezing method are used. An important indicator is the plant's ability to complete its life cycle and enter the dormancy phase in a timely manner, depending on the sum of active temperatures in the region.
Winter hardiness is a key criterion for classifying lilies into hybrid groups. Asiatic hybrids and hybrids of the Martagon group are considered the most resistant, while Oriental hybrids often require covering or digging up. The insufficient winter hardiness of certain groups necessitates the creation of specific conditions, such as ensuring 'dry wintering' to prevent bulb soaking.
General information about the subject — on the page
Winter hardiness.
Selection based on the description text, not on official evaluation: these data are absent from registers. For specific variety details, please refer to its profile.