public class FlowerGarden extends Garden {
   private static FlowerGarden instance=new FlowerGarden();
   private static boolean made = false; 
   
    private FlowerGarden(){
    }

    public static FlowerGarden getInstance(){
        if (!made) {
      made = true;
      return instance;//private constructor, only callable within
      }
    else
      return null; //return no further instances
    }
  public Plant getShade() { return new Plant("Impatiens"); }
  public Plant getCenter() { return new Plant("Zinnia"); }
  public Plant getBorder() { return new Plant("Phlox"); }
}