Growing Orchids in a Northern Climate Greenhouse

Set up your northern climate greenhouse to care for terrestrial orchids. Provide one 4-foot long fluorescent grow light for every five to six orchids you want to grow. Set the greenhouse's humidity to between 30 and 50 percent. Set the temperature to between 60 and 80 degrees Fahrenheit during the spring and summer. Set the temperature to between 40 and 50 degrees Fahrenheit in the fall. Drop the temperature below 32 degrees Fahrenheit for at least three months during the winter.

Choose a type of hardy terrestrial orchid to grow in your northern climate greenhouse. Choose a container for the orchid. The container should be at least 1 gallon and have four to six drainage holes in the bottom.

Fill the container with a mixture of 1 part sand and 1 part peat moss and 1 part compost. Hardy terrestrial orchids need well-draining soil and few nutrients, so this mixture will work well. Dig a hole as deep as the orchid's root ball and twice as wide. Place the orchid into the hole and fill the hole with soil.

Water the terrestrial orchid when the soil mixture is dry about 3 inches deep. Add enough water that it leaks out of the bottom.

Place the orchid in an area it will get full to partial sun throughout the day. Place the orchids 5 to 6 inches below the grow lights if there is not enough natural light in the northern climate greenhouse.

Cut off the flowers after the orchid blooms to prevent it from going to seed.