Chickasaw plums need to have another chickasaw plum for cross pollination. I would get an improved chickasaw plum such as Odom or Guthrie to go along with the existing plant and both plums should start producing. It takes Chickasaws 2 or 3 year to start blooming, but the Odom and Guthrie have a good flavor and are adapted to Florida. Mail Order Natives have both varieties and have good prices. I have some and ordered from them. They are typically out but get new stock throughout the year.