Norfolk Island pine is not an actual pine tree, but rather a relative of the monkey puzzle tree, and often cultivated as a landscape tree in subtropical climates in North America (USDA zones 10 to 11) and grown indoors elsewhere. It has a very straight trunk and pleasingly symmetrical branches covered with short, inward-curving needles, also called leaves.
In other regions, the slow-growing Norfolk Island pine is often grown as a living Christmas tree, frequently decorated with ribbons or ornaments. All too often, the tree is discarded after the holiday season, but it can easily be kept as a permanent foliage plant indoors or planted outdoors when it warms up in the spring. The tree may be toxic to cats and dogs.
|Common Name||Norfolk pine, Norfolk Island pine, Australian pine|
|Botanical Name||Araucaria heterophylla|
|Plant Type||Needled evergreen conifer|
|Mature Size||Up to 200 ft. tall in the wild; 3 to 8 ft. tall indoors|
|Sun Exposure||Full sun; can tolerate shade|
|Soil Type||Sandy, peaty soil; peat-based potting mix|
|Soil pH||4.5-5.5 (acidic)|
|Hardiness Zones||10-11, USDA (grown as a houseplant elsewhere)|
|Native Area||Norfolk Island in the Pacific|
|Toxicity||Mildly toxic to cats and dogs|
Norfolk Island Pine Care
Norfolk Island pines are capable of growing both indoors and outdoors. While they have preferred growing conditions, they are quite forgiving and can thrive in a variety of settings. Outdoors, plant this tree in porous, moderately moist, porous, and sandy soil in a full sun location. Once established, it will tolerate somewhat dry conditions.
When grown as an indoor plant, use a potting mix that is porous, sandy, and slightly acidic. Adding extra peat moss and sand to a standard potting mix will improve its acidity and porosity. Keep the soil damp, but not soggy, and give the plant as much light as possible.
The Norfolk Island pine is a gymnosperm, meaning that a single plant contains male and female reproductive organs. Virtually all Norfolk Island pines are grown from seeds that are usually imported from the Pacific region. Most home growers will never bother with seeds or propagation. Do not attempt to take a cutting or the plant may die.
Although they prefer full sun whenever possible, Norfolk Island pines can also handle relatively long periods (months at a time) in dimmer conditions. Thus, you can keep your potted plant indoors during the winter and then move it to a sunny spot outdoors when the summer comes around.
If your plant begins to stretch while growing inside, the odds are that the combination of low light and heavy fertilizer is causing leggy growth. In that case, cut back on the fertilizer until the plant has more access to sunlight. It's helpful to turn it frequently so every side gets equal light.
These are acid-loving plants. For indoor plants, a peat-based potting mixture is perfect for them as the mix will gradually acidify as the peat breaks down.
When planted outdoors in the garden, this tree prefers a sandy but rich soil, preferably amended with peat.
Norfolk Island pines are somewhat drought- and also salt-tolerant, so they forgiving where water is concerned. It's advisable to let the soil dry out slightly between waterings. This will mean watering the plant once every one to two weeks if it's an indoor plant. Water an indoor plant until excess moisture starts draining out of the bottom of the pot.
Temperature and Humidity
Because they are native to the South Pacific, Norfolk Island pines prefer warmer, wetter climates between 65 and 70 degrees Fahrenheit. They can survive cooler and warmer temperatures briefly but may perish if they experience temperatures below 35 degrees Fahrenheit. To help maintain humidity for indoor plants, mist the plant regularly with a spray bottle or place it over a saucer of water (don't allow its roots to sit in the water, though). However, this plant is more forgiving of dry indoor air than most subtropical plants.
Feed your Norfolk pine with a weak liquid fertilizer throughout the growing season, although it is best to suspend fertilizing in low-light periods.
Norfolk Island pines—especially younger trees—have notoriously weak root systems. To strengthen their roots, make sure you're supplying regular fertilizer and don't hesitate to stake your tree up if it needs support.
Types of Norfolk Island Pines
There is only one variety on the market: Araucaria heterophylla. This plant does not have cultivars or named varieties. A few other species from this family sometimes show up in the trade, mislabeled as the original plant. These include A. columnaris, A. araucana, and A. bidwillii. It's unlikely you'll see these, but if you happen to acquire one, the cultural requirements are similar.
Remove lower branches that have died—a common issue with indoor specimens. It is usually not recommended to trim the top of the tree, but if a potted tree gets too large for its space, cut off the central leader. This will cause the tree to branch out from that point, and while the plant will lose the classic evergreen look, such trimming usually does not affect the health of the tree.
Remove dead and diseased branches from trees grown outdoors, but other than this, no routine pruning is necessary.
Potting and Repotting Norfolk Island Pine
A potted Norfolk Island pine only needs to be repotted when it's root-bound or the roots are beginning to come out of the drainage hole. Young Norfolk Island pines are not very fast growers, so it might be possible to repot your tree every other year instead of every year. As the plant matures, it will begin to grow faster.
Repot your Norfolk Island pine in the springtime, and if your plant has attained a larger size, make sure to use a pot of any material with plenty of heavy items in the mix, such as potting sand, to provide enough weight to keep the plant upright. It will do best in peaty, sandy potting mix that is slightly acidic. Make sure the pot is only a couple of inches larger than the one the plant is coming from, but also make certain it has plenty of drainage holes.
Norfolk pines love the warm weather and can't tolerate temperatures below 35 degrees Fahrenheit. When it is faced with frost, the plant will begin to yellow and die.
Bring a potted tree indoors if it's not already, and keep it away from drafts. Place it in a room with high humidity (difficult to do in a dry home during the winter) and full, bright sunlight. Water only when the surface of the soil is dry to the touch.
Common Pests & Plant Diseases
Norfolk Island Pines are vulnerable to pests including aphids, mealybugs, scale, mites, and whiteflies. If possible, identify the infestation as early as possible and treat it with the least toxic option. A Norfolk pine may also develop a fungal disease from overwatering, such as anthracnose, which can turn entire sections of the tree yellow, brown, and then cause the plant to die.
Common Problems With Norfolk Island Pines
This easy-going tree may encounter a few challenges in its life. The needles will turn different colors to alert you to a problem.
Needles Turning Brown
The tree can't tolerate cold, but it also can't tolerate extreme heat. Wide temperature fluctuations can cause the needles to brown. Brown needles may also indicate that the plant is being overwatered or underwatered, too.
Needles Turning Yellow
If the needles turn yellow, the tree may not be getting enough sunlight. Or, it could be getting too much sunlight. Extreme changes in temperature may also be the culprit turning the needles yellow.
Needles will drop for two reasons: Your tree is either being overwatered or it's not given enough light.
Are Norfolk Island pine trees easy to care for?
Norfolk Island pine trees are easy to care for indoors or outdoors, as long as they enjoy enough humidity.
How long can a Norfolk Island pine live?
When this plant is protected from frost, it is long-living and can reach a lifespan of 150 years.
Do Norfolk Island pines produce cones?
This plant does produce cones, but it won't do so until the plant matures. Females produce cones when the tree is over 15 years old, and males will drop cones on trees over 50 years old.