Cold hardiness in windmill palms (Trachycarpus sp.)

Palms are beneficial for urban ornamental horticulture, since they symbolize the tropics, but only few adapted to temperate climates. Our objective was monitor responses of leaves cold reflected by changes in chlorophyll fluorescence Trachycarpus geminisectus, T. nanus, takil, ukhrulensis, wagnerianus species with use a fluorometer during fall 2018. results indicate that there gradual decline maximum quantum efficiency photosystem II (PSII) represented Fv/Fm values from end September till November This change corresponds well air temperature. Some like ukhrulensis seemed be more sensitive rate greatest this species, also most cases difference significant compared other species. The smallest could observed wagnerianus. However, until middle October after which it not significantly better than performing such as takil and geminisectus. nanus intermediate its values, had lower beginning remaining measurement period different these geminisectus perform on average We found correlation some between minimum temperature (PSII). strongest ukhrulensis. It weaker none takil.