Brightly wrapped Norfolk Island pines given as gifts over the holidays may spark a number of questions.Can they be planted outside?Do they require a lot of light?Read on for answers to these and more questions regarding care of Norfolk Island pines.
What is a Norfolk Island pine?
The small, potted plants that we know as Norfolk Island pines, originated on an uninhabited island near Australia, named by Captain James Cook in 1774. Impressively large "pines" on the island reaching 200 feet in height seemed like a promising choice for ship masts, but they proved too brittle.
Not truly a pine (Pinus), the Norfolk Island pine’s botanical name is Araucaria heterophylla. The genus name is derived from the Araucanian Indians of Chile, where the related monkey puzzle tree (Araucaria araucana) is native.The Greek word heterophylla means "different leaves" and refers to the fact that immature and mature needles of the Norfolk Island pine are shaped differently from each other. Juvenile leaves are needle-like and curve down; adult leaves are more scale-like and overlap.
Cultural Requirements
Norfolk Island pines naturally grow on seaside cliffs and interior rainforests in the temperate South Pacific. This gives us clues as to what kind of environment is favorable for them in the home.
Temperature
It's important to note, that unlike pine trees in the landscape, Norfolk Island pines cannot be kept outdoors year-round in Pennsylvania! The minimum temperature that they can withstand is around 50°F.They prefer a nighttime temperature that is about 10°F colder than daytime.
Light
Place Norfolk Island pines near a bright window—avoid northern exposure, which will result in the least amount of light. If you place them outdoors in summer, note that Norfolk Island pines will grow well in full sun, but would benefit from some shade in the afternoon.
Water and Fertilizer
Water Norfolk Island pines when the surface of the soil seems dry to the touch. The soil should not be constantly saturated. You may fertilize Norfolk Island pines when you see them pushing out new growth but sparing use of fertilizer will keep the plant compact.
Humidity
Best humidity level for Norfolk Island pines would be above 50%, which is difficult to achieve in homes, especially in winter.(Misting and placing the plant on a tray of wet pebbles do not measurably raise humidity levels.) At least keep the plant away from a forced air vent in winter. Grouping it with other plants may help increase humidity a little.Using a humidifier or growing Norfolk Island pines in a greenhouse would be ideal.
Soil and Repotting
Experts recommend amending potting soil with a small percentage of sand and peat moss for Norfolk Island pines. Plants should be repotted every three or four years when roots become visible above the surface of the soil.
Problems with Norfolk Island Pines
Norfolk Island pines are not especially plagued by pests but may become unsightly for other reasons. I have had issues with Norfolk Island pines developing a permanent bend in the trunk; this can be avoided by rotating the plant weekly. Browning and dropping lower branches are also common problems. This may be caused by low humidity; regular watering can help stave this off. Excessive fertilizer can also cause branches to drop.
Pruning
Pruning a Norfolk Island pine is generally not recommended.You may cut off dead branches or tips of branches to tidy up the tree’s appearance, but pruning will not result in a flush of new growth, as you may have experienced with deciduous plants. Given the tree's propensity to grow to a great height in its natural environment, at some point you may find yourself wondering if can cut the tree back before it goes through the roof! This may be the time to compost your Norfolk Island pine and start over or find it a home in a building with higher ceilings. I found very few articles that offered instructions for pruning a Norfolk Island pine to reduce size. If you are brave enough to try it, I recommend Dealing With Your Ginormous Norfolk Island Pine by Steve Bender, aka The Grumpy Gardener.
Can I decorate my Norfolk Island pine?
Yes! You may have bought or received the plant decorated for the winter holidays.Since the branches are soft, use lightweight ornaments. If you decorate with lights, use a string of LEDs, which will not give off heat.
