I planted the Yellow and the Pink Allamanda last year.The pink ones are coming back faster than the yellow ones. .The Yellow ones had winter damage.I have seen them at Houston Garden Center last year,but I bought them from Nelson Garden in Katy.

Do you mean Nelson Water Gardens? I know there is some kind of nursery company that is also named Nelson's but I didn't think they were in Katy.
So I take it neither of them are invasive for you?

Two people on Dave's garden said they showed serious potential for invasiveness. I'd keep them containered for a couple years and keep an eye out for reports of invasiveness. I'd also keep them away from my home and valuable trees.
The plant,from the milkweed family, is poisonous. It has spikey balls to fertilize and self sows, it's a member of the carrion flower family...do the blooms stink? Will the blooms stink is profusion? Will the spikey ball seed pods fall where barefoot folks walk? It's sap is irritating to the skin how will that affect the person who has to prune this fast growing,large vine? You could always put it in a large (build from wood) container with a solid but well drained bottom (pipes out the sides with holes drilled in the top, like a leach line for septic) to control it and see how it goes. It sounds very pretty and hardy. I would be reluctant to put this plant in the ground. It sounds a lot like trumpet creeper to me.

Yes,I bought it from Nelson water garden.Due to the winter freeze,it has only just started to grow.I just got gallon sized pot last year,so it has not grown too much.

I've had it 2 or 3 different times, and was disappointed every time. It made a nice vine, pretty foliage, but few blooms. It wasn't invasive, died at the first freeze, and didn't return in the spring. I have the bush allamanda, and like it real well. It blooms continuously, doesn't mind pruning, and returns in the spring.
Jim