From a tire professional who works with these tires everyday.
I know a man here who puts in water in the spring and drains it out in the fall. Milton makes an adapter for a garden hose to tractor valve stem. Wouldn't be any problem as long as you get it drained before freezing. Draining is no problem, just park valve stem on the bottom, remove the inner valve stem and stand back. Inflate when done. What little water is left would be no problem.