Monday, December 20, 2010

Norfolk Island Pine - Know the Risks Before You Plant

First of all – I’d like to welcome those of you that have navigated your way here from the Galveston Gardening article in Coast Magazine. We invite you to subscribe to have the GG Blog delivered to your email address.

You won’t find it on anyone’s list of recommended trees but the Norfolk Island Pine (Araucaria heterophylla) is certainly a favorite among gardeners throughout Galveston and the Texas Upper Gulf Coast. The biggest concern about this plant is its lack of cold tolerance – and in all likelihood they will freeze one of these days.

On the plus side, they survived all that Ike had to dish out (i.e. salt and wind), are pretty fast growers (once planted in the ground) and they did survive the winter of 2009 (one of our coldest in recent memory). So if you understand the risk of freezing, the Norfolk Island Pine is a very interesting selection for the area.

Now for a few details. First of all the Norfolk Island Pine isn’t actually a pine (Pinus). It belongs to another plant family that contains some familiar members like the monky puzzle tree. The Norfolk Island Pine is native to – you guessed it - Norfolk Island. A tiny island paradise in the southern Pacific Ocean, east of Australia. This island was originally discovered by Captain James Cook and named for Great Britain’s Duchess of Norfolk.

The Norfolk Island Pine is rated for hardiness zones 10 – 11, which means we’re right on the edge. Damage can occur at temperatures below 40° F but in a protected area these plants seem to take much colder weather. Well-established specimens are also a bit tougher. Their ability to survive Ike’s saltwater surge, the drought that preceded the storm and hurricane force winds was impressive.

These plants like full sun but will perform in full to partial shade. Plants tend to have “droopy” limbs when grown under limited light conditions. The Norfolk Island Pine isn’t too picky about soil type but thrive in a well drained location with a little supplemental water applied now and again. Well cared for trees have an impressive growth rate.

Many Norfolk Island Pines on Galveston Island have topped 100’ in height. While doing the tree survey following hurricane Ike, my Texas Forest Service friends suggested that some of these specimens could easily be state record sized trees – if the species qualified. Look up and you can see Norfolk Island tree tops all over town.

That being said, there are a few considerations when planting a Norfolk Island Pine in the landscape. Since they do get so tall, scale may be an issue. A small tree that starts out looking good can develop in to an over sized monster that dwarfs the residence. Consider the ultimate size of the tree before selecting a location. A smaller sized tree may be a better solution.

Norfolk Island Pines are grown primarily as table-top or living Christmas Trees. In fact, I don’t know of a single Texas nursery that grows these plants specifically for use in the landscape. They are very slow growers in a container and may take as long as 3 years from seed to a finished 10” pot (the size you see most often in stores). One way growers speed up finish time is to place 2-3 plants in the pot. You can see many of these multi-trunk plants in landscapes throughout the area.

Since the Norfolk Island Pine is a seasonal item, available primarily around the holidays, NOW is the time to pick up a plant or 2 if you’re planning on including one in the landscape. They’ll be much harder to find in a few months. Enjoy it as a Christmas tree and plant later in the spring when the threat of cold weather has passed. It the pot has multiple trunks, keep the largest and cut off the rest.

Remember – the Norfolk Island Pine is not on the list of recommended trees for Galveston County. BUT if you’re prepared to deal with the risk of cold weather damage/freezing it is a pretty cool plant.