Season the ducks with salt and pepper, then rub with thyme leaves. Stuff half the apple in the cavities of the ducks. Pierce the skin with a fork and dot the skin with butter.
Place the ducks, on a rack in a roasting pan. Pour the water and wine into the pan.
Roast in oven for 1 1/2 hours or until an instant read thermometer placed in the thigh registers 180 degrees F. Baste occasionally, adding water if needed. During the last 20 minutes of cooking, place rest of the apples in the pan. When the ducks are fully cooked, remove them from the oven and let them rest for 15 minutes before carving. Mix the pan apples with the sour cream and serve with the carved meat.