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

    private VeggieGarden(){
    }

    public static VeggieGarden 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("Broccoli"); }
  public Plant getCenter() { return new Plant("Corn"); }
  public Plant getBorder() { return new Plant("Peas"); }
}