By Sandy Feather
Penn State Extension
Q. I received a Norfolk Island pine as a Christmas gift and would like to know how to care for it properly. Can I plant it outside in the spring?
A. Norfolk Island pines (Araucaria heterophylla) can make attractive, durable houseplants and are often sold as already decorated Christmas trees around the holidays. They grow slowly, perhaps 3 to 6 inches annually, and are well suited for indoor culture. Norfolk Island pines are not hardy in the northeastern US, but they are 200-foot-tall giants in their native habitat off the eastern coast of Australia.
They are hardy in USDA Zones 10-11 in the United States and begin to show signs of cold injury below 40 degrees.
These plants perform best in bright light, with at least two or three hours of direct sun daily. An east-facing window should be ideal. Turn the plant a quarter of a turn weekly to keep it from getting lopsided as it grows toward the sun. They should be fine in temperatures that we find comfortable indoors, although they appreciate slightly cooler temperatures at night. A range between 60 and 70 degrees is best.
Norfolk Island Pine decorated with a red holiday bow
The biggest challenge to successful indoor cultivation is dry indoor winter air. Norfolk Island pines prefer humidity in the range of 50 percent, while 15 percent is the norm in most houses during winter. Running a humidifier can solve this problem.
If that is not an option, place the pot on pebbles in a saucer with water in it. It is important to keep the bottom of the pot above the water so that the plant is not sitting in water constantly, or the roots will quickly rot.
Another way to increase humidity is to group houseplants together. Because plants lose moisture through their leaves constantly, the humidity is higher in the microclimate created by grouping them.
Norfolk Island pines prefer evenly moist but never saturated soil. Allow the top inch of soil to dry out between waterings. The best way to water this plant -- and most houseplants -- is to place the pot in a sink or bathtub and water until it comes out of the drainage holes in the bottom of the pot. Once the pot has finished draining, take it back to its usual place. If that is not an option, be sure to empty the saucer under the pot. If the pot is too heavy to lift, remove the excess water with a siphon pump or a turkey baster. Houseplants usually respond to higher light levels that come with spring by putting on new growth.
Once your Norfolk Island pine is actively growing, you can use a water-soluble fertilizer formulated for foliage plants. Something such as fish emulsion or Peter's 20-20-20, used according to label directions, is fine. Stop fertilizing in September and do not start again until the plant starts putting on new growth in spring.