Drain Valves

[SLI]

I am still in the planning stages of my first irrigation system. What I need to know is, do I need to install drain valves for a system in North Alabama? We get some very cold temperatures here in the Winter, but usually for a short period of time. If drain valves are needed, should I go with manual or automatic?

[Wet_Boots]

Neither. Use an air compressor to winterize the system, by blowing the water out the pipes and heads.