Oleanders must pass Valley shiver test

Q: A relative of mine from New Orleans has sent me an oleander plant for my yard. Can I plant it now and will I need to protect it over the winter? Also, I have heard they are poisonous so is there anything special I should do about that? Thank you. - Regina B.

A: Oleanders have become a hot topic recently. I have had several people stop and ask me about growing them in the Tennessee Valley, and another gardener wrote asking about the toxicity of the plants.

As to whether they will grow here - only time will tell. The textbook answer is "No, they shouldn't survive a typical Zone 7 winter of North Alabama." However, it seems that we have not had a typical Zone 7 winter in quite some time, and I know of several gardeners who have had their plants come back the past few years. How long we can count on that is up to our weather patterns and the severity of our winters.

Oleander (Nerium oleander NE-ri-um o-LE-an-der) is native to Southern Asia and the Mediterranean region of Europe. It is a member of the Apocynaceae family that is often referred to as the dogbane family. Most of the genera in this family are native to the tropics or subtropics but a few members are found growing in our woodlands like bluestar (Amsonia hubrechtii) and periwinkle (Vinca minor). The lovely plumeria or frangipani that the beautiful Hawaiian leis are made of is also in this family.

One of the characteristics of the family is a sticky, milky sap that oozes from the stems or leaves when bruised, crushed or cut. This sap can cause skin irritations much like poison ivy but that is not where the true danger lies (more on that later).

I have seen oleanders growing all over the Gulf Coast region with little or no care in the landscape. Plants can get quite large, up to 12 feet tall and 6 feet across with evergreen foliage that resembles a willow leaf. The true beauty in this plant resides in the showy flowers that are visible for a long period of time. The dominant flower colors are red, pink and white but you can also find cultivars with blooms of peach, yellow, apricot and lilac. There are almost 500 cultivars that have been registered but you will find only a few selections available at garden centers.

In the coastal region, oleanders will be evergreen with some foliar damage below 20 degrees F. Dieback will occur at 15 degrees with plants being killed below 10 degrees. However, it is not just how cold it gets that will determine hardiness. Like many tender plants, most damage occurs when they have begun to come out of dormancy and are then hit with a late freeze. Since the sap is flowing, the plants are much more susceptible to damage than when we are in mid-January and temperatures are in the teens.

My opinion on growing tender plants like this is to go ahead and try it knowing that it may not survive a harsh winter. You can take some measures by adding extra mulch such as pine straw around the base for extra insulation but realize you are pushing the envelope in growing one in this area. One other alternative is to keep it in a large container and treat it like a tropical hibiscus - put it in an unheated garage or storeroom for the winter.

Now your question is should I plant the one I have right now or wait? Normally I would say plant now; this is perfect planting weather. However, it may be more prudent to wait and plant in spring as a precaution. Just keep your container from freezing over the winter and you will be fine.

Lastly, we get to the issue of toxicity and truly how poisonous are oleanders. The short answer is that they are highly toxic and all plant parts contain some poisonous elements.

From ancient times there have been numerous accounts of deaths and suicides from drinking oleander tea. The story most often shared is about the troop of Boy Scouts who roasted their hot dogs using sticks of oleander at a campout and they all died from ingesting the poison through the hot dogs. This one probably falls in the "urban legend" category since the myth-buster Web site www.snopes.com cannot verify the claim.

However, there have been other (not many) reported deaths from ingesting the leaves. People have even talked about having violent reactions to inhaling the smoke from burning branches of oleander. With that being said, it looks like a plant to definitely look at and not touch (definitely not eat), so if you are concerned about the prospect of children or animals chewing the leaves I would keep it out of your yard. I hope this helps and thanks for reading.

Things to do:

If raking leaves is not your thing, be sure and mulch them using the lawnmower so that they will not pile up and smother your grass.

Plant spring flowering bulbs (tulips, daffodils, crocus, wood hyacinths, Spanish bluebells, spring snowflakes, etc.) all month long.

E-mail Harvey Cotten at harvey.cotten@htimes.com, or write to Harvey Cotten c/o The Huntsville Times, P.O. Box 1487 West Station, Huntsville 35807.