As long as freeways have been getting landscaped, oleanders have been contributing their profuse white, pink and red bloom. Heat, exposure and lack of moisture do not seem to bother them. They have become less common recently only because of new diseases that had never before been problematic. The diseases do not necessarily kill all oleanders everywhere, but are serious problems where the nurseries that grow most oleander are located.
The largest oleanders can get more than fifteen feet tall, and can be pruned up as small trees with multiple trunks. Oleander trees with single trunks almost never stand up straight, and do not want to give up their stakes. Because flower clusters develop at the ends of new growth, frequent exterior pruning or shearing inhibits bloom. Dwarf cultivars that are naturally proportionate to their space will bloom better than larger types that need to be pruned for confinement.
Oleander flowers are about an inch or two wide, with five petals, although some have ruffly ‘double’ flowers. Unfortunately, double flowers tend to hang on as they deteriorate after bloom. Some oleanders are slightly fragrant. The name ‘oleander’ is derived from the similarity of their leaves to those of olive trees (‘Olea‘), although oleander leaves can get three times as long.
Tony Tomeo 
Oleanders are intimately connected to the history of Galveston. You can read a bit more about the history here, but this gives a hint of it all:
“The first Oleanders came to subtropical Galveston in 1841. Joseph Osterman, a prominent merchant, brought them aboard his sailing ship from Jamaica to his wife and to his sister-in-law, Mrs. Isadore Dyer…
“As early as 1846, note was taken of the yards in Galveston with oleanders and roses in full bloom and the contribution they made to the beauty of the city. Oleanders flourished in these early days of the city and were able to withstand the subtropical weather, the alkaline soil, and the salt spray. Therefore, it was logical for oleanders to be chosen as one of the predominent plants to be used in the replanting of the city following the destruction of the 1900 hurricane and grade raising that covered the existing vegetation with sand.”
After hurricane Ike, the Oleanders were replanted, but today the dwarf varieties are more used.
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Well, at least they are appreciated somewhere. They are more common here than they are popular, and are now becoming less common because of a nasty disease that has been killing them. Compared to the trendy plants, oleander is more colorful, and is at least as undemanding.
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I was also going to mention Galveston, but Shoreacres gave a good history.
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Yes, that is fascinating, but not surprising that roses are overrated relative to oleander.
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Nice, but whenever I see Oleander now I think of the novel White Oleander where the plant is used to poison and kill someone.
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There are so many more toxic plants that could have been more effective. Although toxic, oleander poisoning is uncommon.
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Oleanders are great freeway divider pants, but need to stay there — they are highly poisonous if ingested, either accidentally or deliberately!
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Unfortunately, other plants are even more toxic, but not commonly known as such. Oleander gets most of the blame.
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I like to see oleanders but they are rare here. Your picture is marvellous. I love the light on the petals.
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Cool. I was not satisfied with the picture because it does not show much of what the rest of the shrubbery looks like. I needed to choose between a picture of the shrubbery or a close up of the bloom.
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