Monkey Puzzle Tree in Vancouver, BC

Closeup of scale-like foliage

Monkey puzzle tree or Chilian pine (Araucaria araucana) is an evergreen conifer that is native to forested volcanic slopes of the Andes Mountains in Chile and Argentina (USDA Zone 7b-11). It is the national tree of Chile. Monkey puzzle typically grows to 60-70 feet tall and 30-35 feet wide, but may reach heights greater than 100 feet in its native habitat.

It displays a unique loose pyramidal form when young, but develops a rounded canopy along with loss of the lower branches as the tree ages. Horizontal, upward-arching branches are arranged in whorls around the trunk. Bark is gray-brown and ridged.

On the straight trunk, 2-inch long evergreen leaves are glossy, dark green, triangular-shaped, sharp tipped, and closely overlap one another. Individual leaves are leathery and may persist for 10 – 15 years. The horizontal branches are produced in tiers and develop few side branches.

Trees are dioecious (separate male and female trees). The female cones are globular and up to 8 inches in diameter; male cone is cylindrical and up to 5 inches long. Seeds (pinones) are edible and reminiscent of pine nuts.

It is best grown in deep, moderately fertile, evenly moist, well-drained soils and in full sun to part shade. Trees perform well in a variety of different soils as long as sites are well-drained. Trees perform much better in mild summers than in hot climates. In northerly areas, trees may be grown in containers and brought indoors overwinter in bright indirect sunlight.

The tree is rarely troubled by serious insect or disease problems. Needle necrosis and leaf spots. Mealybugs, scales and thrips are occasional pests.

Monkey puzzle is related Norfolk Island pine (A. heterophylla), a popular house plant seen for sale at garden shops during the winter holiday season in the U’S. and Canada.