Catteleya Orchids Require Short Days to Flower

A few orchid species require short-day photoperiods in conjunction with cool temperatures to flower, such as some species of Cattleya, Dendrobium, and potentially some species of Phalaenopsis.

For these types, you’ll need to combine cooler temperatures and shorter daylengths from midfall through winter, then lengthen your lighting period again in spring.

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