The Norfolk pine (Araucaria heterophylla) is widely sold across the United States every Christmas season as a tiny holiday house plant tree. Native to the Norfolk Islands and Australia, it excels in tropical and sub-tropical areas but must be grown as a house plant in other areas.
Grown in the wild, the trees will tower 220 feet in height with a trunk that is often 10 feet in width. The tree stays relatively small when grown as a house plant and normally grows only 3 to 6 inches per year.
The Norfolk pine requires several hours of direct sunlight during the day. Inadequate sunlight will result in the limbs drying up and falling from the tree. Rotate house Norfolk pines in the window so the tree does not begin to lean towards the light. During the warm summer months, the trees enjoy being carried outside and placed in the sun.
The Norfolk pine prefers acidic soil. A potting medium should contain 75 percent peat moss to meet the plants requirements. Sand can also be added to the soil to help drainage and offer support to the tree's trunk.
An ideal nighttime temperature ranges from 50 to 55 degrees F. Daytime temperatures between 68 degrees F to 72 degrees F works well for the Norfolk pine. It can tolerate a dramatic temperature drop to 45 degrees F with ease. Exceedingly high temperatures that top 95 degrees F can cause the tips of the branches to begin drying out.
Water the Norfolk pine when the soil feels dry to the touch. Allow ample water to run through the pot and out. Do not allow the pot to sit in a saucer or pan of water. Norfolk pines do not enjoy wet roots and will easily perish in standing water.
Fertilzing and Potting
Fertilize the Norfolk pine every three or four months using a basic indoor house plant fertilizer. Follow the directions on the label for application instructions. Re-pot the Norfolk pine every three or four years. The tree can be root bound, with no adverse effects.
The Norfolk pine requires high humidity to truly thrive in a household environment. They prefer the humidity level to hover around 50 percent. Running a humidifier to meet the trees needs is often required in dry areas or the tree will begin to dry out and lose its needles.