Tuesday, March 10, 2020

Growing and Caring for Norfolk Island Pine

Growing and Caring for Norfolk Island Pine Araucaria heterophylla, or Norfolk Island pine or Australian pine, is a southern hemisphere conifer native to the Norfolk Islands and Australia. Technically, its not a real pine. Norfolk Island Pine is one of the few conifers able to adapt to inside the home and is able to tolerate relatively low light levels. In its native habitat, this tree may reach 200 feet in height with 15-pound cones. The tree will grow outside in the United States but only in the semi-tropics of Florida. Specifics Scientific name: Araucaria heterophyllaPronunciation: air-ah-KAIR-ee-uh het-er-oh-FILL-uhCommon name(s): Norfolk Island Pine, Australian PineFamily: AraucariaceaeUSDA hardiness zones: South tip of Florida and California, zone 11Origin: not native to North AmericaUses: specimen, house plantAvailability: generally available in many areas within its hardiness range - especially during Christmas holidays. Pruning As Norfolk pine grows upward, the trunk thickens and the pine limbs increase in size. You should never cut their growing tips off and only rarely trim side branches for balance. A symmetrical look can be maintained by turning the plant regularly toward the sun. The lower branches and limbs tend to shed dry, brown needles when dehydrated and need pruning. The dry needles will not come back nor will lower limbs. These drying needles and dying limbs suggest drying out so follow watering instructions. The only maintenance pruning to be done is the removal of dead lower branches. Comments From Experts Extension Nursery Specialist Dr. Leonard Perry: If you want to invest in a houseplant with a future, buy a Norfolk Island pine. It requires minimal care, and because it grows slowly will remain small and attractive for many years indoors. Horticulturist Rosie Lerner: The Norfolk Island pine has grown in popularity as a live indoor Christmas tree. Its lush green twigs of soft needles provide a lovely backdrop for festive holiday ornaments. Moisture Norfolk pines have distinctively flat, whorled snow-flake like branches and short soft needles. They enjoy humid environments. As they age, and with the lack of humidity, the needles along the trunk will fall off. Mist spraying and a rocky moisture bed can increase humidity but never leave moisture around the roots. Just like under-watering, too much water will result in sporadic bright yellow needle clusters that come off very easily and dont come back. Check to make sure the plant is not standing in lots of water. It is actually inhibiting root water uptake, increasing root rot and, like lack of moisture is not good. These plants do best with consistency so stay on a weekly watering schedule - not too much and not too little h2o. You can get by with less during the dormant winter months. Fertilization Norfolk Island pines dont require frequent fertilization but when you do, use only at half the normal recommended rate. You can also use any complete soluble fertilizer including liquid foliar plant food applied as a mist for enhanced foliage response. Fertilize older plants every three to four months and repotted or newly purchased plants every four to six months. Try to limit the times you move your tree to a  new container as they have a weak root system which can be harmed by rough movement.  Norfolk Island pines need only be repotted every three to four years using a commercially available potting mixture. Culture Light requirement: tree grows in full sunSoil tolerances: clay; loam; sand; acidic; alkaline; well-drainedDrought tolerance: highAerosol salt tolerance: moderateSoil salt tolerance: good In Depth Although Norfolk pines provide some shade, they are not suitable for patios or terraces because they are too large and large surface roots are common. Obviously, this only applies to people growing the tree in south Florida. For the rest of us, moving a potted tree outside to partially shaded sun through spring and summer is a good thing. Many people forget how tall these trees grow. They often have an attractive pyramidal form (like a fir or spruce tree) when they are small, but they quickly grow too tall for most residential sites. They can live as a houseplant for a long time if not over-watered but rarely grow more than 5 or 6 feet tall. Growing best in full sun locations, this tree thrives on a variety of soils and is moderately salt tolerant. Young plants should be watered well, especially during periods of drought. Be sure to prune out multiple trunks or leaders as they should be grown with one central leader.​​ Propagation is by seeds or cuttings of erect shoot tips only.