Araucaria heterophylla is a relic of an ancient family, Araucariaceae, from 200 million years ago (the Jurassic era). It was isolated to Norfolk Island before being popularly used as a coastal tree or tiny indoor Christmas tree, mostly in North America. The female cones are massive, and the foliage changes as the tree matures. It has a unique shape, although juveniles look very similar to A. columnaris. Sometimes known as the ‘Star Pine’ due to its unique growth patterns when young, this tree is very frequently sold during the holiday season. Many are commonly grown in greenhouses, where they can grow beyond 3 meters tall.
Araucaria heterophylla (Norfolk Island Pine, Cook Pine, New Caledonia Pine, Star Pine) [A. excelsa]
Native: New Caledonia/Norfolk Island
Hardiness Zones: 9b-11
Height: to 24 meters, sometimes larger in native habitat
Diameter: usually to 6m
Root System: fairly shallow, weak (intolerant of mechanical damage)
Growth Rate: extremely, slow indoors (adding new foliage annually at best), rapid outside (specifics not stated)
Age: to 150 years typically
Tolerates: drought, most soils once established, mild salt tolerance, strong wind
Problems (major): none identified
Problems (minor): Sooty mold, leaf spot, scale, requires high humidity
Soil requirements: almost any once established, proper drainage required, prefers medium/loamy soils
Air Requirements: Humidity should remain constantly above 50% for proper growth indoors. Air temperature should never drop below 10 degrees Celsius (50 degrees Fahrenheit).
Watering requirement: medium, low for house-bound plants
Sun requirement: full sun (in order to reach maximum height), part shade (these trees can (but VERY rarely) reach 18-24 meters (60-80 feet) tall with part shade)
Leaves: vary with maturity (hence ‘heterophylla’), young needles awl-shaped and cover entire branch, mature needles arranged spirally, curled inwards, frequently overlap, appear very similar to Araucaria columnaris
Cones (male): small, initially yellow turning brown at maturity, longer than female cones, grow in clusters, produced after 15 years ideally, prolific development usually every 5 years
Cones (female): large, ovular, globose, initially green (before changing to brown), ideally produced after 40 years, around 12 centimeters long and 15 centimeters wide, to nearly 7kg
Seeds require stratification: no
Monoecious or Dioecious: dioecious, some accounts claim monoecious specimens
Norfolk Island Pines belong to the Araucaria genus (Araucariaceae family), which dates back 200 million years to the Jurassic era. Norfolk Island Pines were discovered by Captain Cook on his second journey around the Pacific, when he accidentally encountered Norfolk Island. A. heterophylla grew almost solely on Norfolk Island, until they were grown abroad for use as holiday trees or ornmental trees in warmer climates. Female cones are massive, weighing up to 6.8 kilograms (15 pounds), although cone production is very rare indoors. A. heterophylla looks nearly identical to A. columnaris when young, differing primarily in shape as they age. The foliage change forms as the tree matures. This is not a true pine.
The wood is fairly sturdy, although timber usage is mostly restricted to Norfolk Island. This tree is used as a Christmas tree, especially among North Americans, to be grown indoors. This tree is wonderful coastal tree for its great salt, wind, and drought resistance. It is grown as an ornmanetal tree where permitted, although it is not usually intended as a shade tree.
A. heterophylla stem with branches (as the tree increases in size, the needles become less apparent on the stem)
All of the images provided were taken by me. They may be used for educational/informational purposes only, provided that this article/online journal is appropriately cited first.