What Is the Temperature of an Orchid Greenhouse?

Average Temperature Range for Orchids

• The most readily available orchids on the market are tropicals. The comfort range for these orchids is 60 to 85 degrees Fahrenheit. This temperature range is easily and inexpensively achieved in the Bahamas but costly in Norway. Choose orchids for your greenhouse collection with your temperate zone in mind.

Choices for a Colder Greenhouse

• Four types of orchids that will tolerate, even enjoy, cooler temperatures are the cymbidiums, the dendrobiums, the cattleyas and the masdevallias. These are easily found through retail establishments, specialty mail-order catalogues and online. All of the four types listed above will happily tolerate temperatures down to 48 degrees Fahrenheit. To initiate its bloom cycle, the cymbidium requires four to six weeks in the fall when temperatures remain in the 38- to 48-degree Fahrenheit range.

Pitfall of a Cooler Greenhouse

• Bacteria adore nothing more than a cool, wet, dark greenhouse. If the greenhouse is cool, the watering schedule must be adjusted so that the orchids have time to dry before darkness. Use tepid water to spray the plants, and water them only on sunny days. Water them early in the day so they'll have time to dry before dusk. Preventing illness is much easier than fighting it.