Q: I am writing to you hoping you know anything about the Royal Poinciana tree. It is very beautiful and it grows in Puerto Rico. You can see it along the country roads, with bright orange flowers starting in March. It has leaves very similar to the mimosa that grows here in Georgia. I have two seedlings about three feet growing in a pot. Can I leave them outside in Newnan during the winter?
A: You are sharp to notice that the leaves of the poinciana are similar to the leaves of mimosa. Both are members of the legume family – which, oddly enough, also includes field peas and kudzu. All legumes can convert gaseous nitrogen from the air into plant nitrogen to feed themselves. Although it gets pretty hot in Coweta County in the summer, it doesn’t stay hot in the winter. Your Royal Poinciana will freeze to death if left outdoors.
You can try bringing it indoors in a large pot but make sure it gets lots of light during the winter. Since it wants to be a tree, you will have to constantly pinch back the branch tips each time they have grown a few inches to keep the plant small. However, if you pinch back the tips, the hormones that signal flowering may never be produced and you’ll not get the beautiful orange blooms you miss. Sad to say, having this plant in your neighborhood may be an impossible dream without investing in a greenhouse.