Whether grown in containers or landscapes, Norfolk Island pines (Araucaria heterophylla) beautify their surroundings. These ubiquitous tabletop Christmas trees become magnificent specimens when grown outside in U.S. Department of Agriculture plant hardiness zones 10 and 11. In regards to dirt, Norfolk Island pines adapt easily, however they do have particular needs. Understanding the tree’s preferences will be able to allow you to provide proper dirt for your own tree.
Island Beginnings
Norfolk Island pine’s plant family dates back to prehistoric times. Native to Norfolk Island, a small island east of Australia, the trees are now protected there. At the sandy, coastal soils, they grow up to 200 feet tall with 10-foot-diameter trunks. In U.S. landscapes, Norfolks can grow 24 inches per year to reach 100 feet in height and spread 60 feet. When ancient roots meet proper soil, the trees reside over 150 years. Given space in containers, long-lived Norfolks grow up to 20 feet tall.
Landscape Plantings
When planting Norfolk Island pine from the ground, it may seem wise to include sand and replicate island beaches. But Norfolk Island pine adapts readily to all ground types. Amending soil can be detrimental, especially when trees have weak root systems, as do Norfolk Island pines. Amendments create a border between the planting hole and native soil. Roots grow nicely till they hit the wall. They then creep along the edge and circle back from where they came. The plant becomes root bound within the hole. Whatever the soil type, Norfolk Island pine can adapt so long as the ground is well drained.
Container Growing
If you develop Norfolk Island pine in a container, superb drainage is vital. The trees thrive in well-drained containers, staying in the same pot for several years. Due to the weak root system, they rarely need repotting, but tilting may cause difficulties. Soil must be able to provide support or the tree must be staked. A mixture of equal parts potting soil, peat and mud gives a acceptable medium for root support and growth. Norfolk Island pines succeed in both acidic and alkaline pH soils. No additional adjustments should be required.
Norfolk Care
When caring for a container Norfolk, water the tree only when the soil becomes dry to the touch. Water thoroughly so water runs through to the saucer beneath. Discard the surplus; never allow the tree sit in water. Supply extra humidity by placing a water-filled saucer of seams beneath the tree. From the landscape, give Norfolk Island pine full sunlight. At your home, provide it just as much bright light as your home allows. Turn the tree regularly so the textured branches maintain the gorgeous symmetry for which they’re known.