Wednesday, August 15, 2007

Nerium Oleander: Vulnerable After All

Nerium oleander 'Petite Pink'

I have conflicted feelings about the Nerium oleander. When I purchased my property, the front landscaping was already in, and it included nine Nerium oleander ‘Petite Pink’ dwarf oleander shrubs. Never a fan, I immediately eliminated four that were awkwardly located. The remaining five line the side of my driveway, and I left them there because they gave the area a nice symmetry.

My feelings about oleander go back a long way. As a child, an uncle told me that my father’s triplet brother died at eleven from falling on an oleander stick. I learned later that was untrue, but the story certainly tainted my perception of the plant. As a teen, my best friend’s plumber uncle told me that his major income came from repairing sewer lines damaged by invasive oleander roots. Then I learned that once planted, oleander is almost impossible to get rid of because of its ability to tolerate extreme heat, cold, drought and pest and pestilence. More on that later.

The oleander’s origin is the Middle East and Asia. It thrives in USDA Zones 8b to 11 and it is used extensively in the Southwest as a freeway planting. It flowers most of the year and thrives on neglect. It has tough, leathery leaves and can grow to 30 feet over a period of years.

Huge oleander stands are found throughout Phoenix. The plantings serve as a natural fence between properties and as a buffer from traffic noise, and define the character and charm of several popular historic neighborhoods around town.

The dwarf variety is more common in newer neighborhoods now that folks are familiar with the downside of the oleander. The small size is controlled by pruning a couple of times a year. In addition, propagation is a snap, literally. Just snap off a twig and stick it in the ground and stand back.

Oleander is toxic. It should not be eaten—more of a problem with pets than with humans, I would hope. Some people are allergic and have skin reactions just touching the cuttings. The smoke from burning oleanders is especially toxic. Earlier this year, a fire occurred in a Phoenix neighborhood and the fire department called for an evacuation of the area until the fire was under control, all because of the burning oleander.

It turns out that oleander is subject to pest and pestilence after all. There is a bacterium spread by a common sucking insect, the smoke tree sharpshooter. The bacterium causes Oleander Leaf Scorch, which eventually kills the plant. Once the plant is infected, it’s a goner. Whole stands of oleander have died out in California, and the problem has now begun in Arizona. If it finally hits some of those old Phoenix neighborhoods, it will change the face of the city. Although I’ve never cared for the plant, I would sure hate to see that happen.


RUTH said...

I keep my Oleander in pots so don't have too much of a problem with them. I have successfully rooted cuttings too. I found this post really informative...thanks for sharing. :o)

kate said...

I had no idea that a burning oleander was toxic. Our environments are so different that the thought of having oleanders growing outside is a novelty. I have one in a big pot and it seems to get infested with mealy bugs every year.

It's interesting how we get an idea about a tree/shrub/plant in our heads and it colours our outlook on them forever... kind of like the Dieffenbachia for me.

The Oleander pestilence there reminds me of Dutch Elm disease which wiped out lots of the trees lining our city streets.

sisah said...

Interesting reading your thoughts and experiences about oleander, which I considered to be quite an ordinary (patio) plant: every neighbour here seems to have one, everybody grows it in huge pots and everybody seems to have problems to find a place to overwinter it, and everybody seems to talk about the pests it gets during that time, as obviously this plant doesn´t like to stay the winters in dark rooms, in dry air . No wonder it attracts scale insects and other pests.So I never wanted one...but I loved to see all these huge bushes on a leave in Italy, where they even grow at the sides of motorways.
I knew they are toxic, but I never expected it to become dangerous when inhaling the fume of it.
I come to the conclusion, Oleander is not at all the ordinary plant, as I thought it is.Thank you for your report!