The first thing you learn about oleanders when you grow up in Phoenix is that they are poisonous. I used to think a lot about this when I was sent out to cut the huge oleander hedge that we had around our yard. I always wondered if I was going to die. Well, yes they are poisonous but only if you eat the plants. These are very resilient plants and can survive almost anywhere in the desert Southwest. They are also very invasive and have roots that can clog pipes. They are pretty when in bloom.