I'm glad that worked - this time. Some diesels don't seem to mind the cold at all, but many are a little finicky. Why fight it? Be easy on yourself and easy on your tractor.
1. Have a healthy, high capacity battery.
2. Have a good way to heat the engine.
a. An OEM block heater (can be a tricky install).
b. A glue on pad heater (easier install - see below).
c. Any number of electric heater/hairdryer/heat lamp/torpedo heater methods as referenced in this thread.
A 500 Watt pad heater like this can be purchased at auto parts stores, Amazon. ebay, etc.
Zerostart / Wolverine (5"x7") 500 Watt heating unit designed to work in the coldest of climates. The heater is attached directly to the pan or tank with a special 3M adhesive. No cutting hoses, removing frost plugs, or loss of anti-freeze 菱eats 6 quarts of oil from -40 コF to +60 コF in about an hour.