Thanks to the Astros Director of Social Media Kelly George for getting us this information.
Staff + Pitchers & Catchers - March 2
Positions Players - March 6
Astros Minor League Spring Training games start March 14. The Washington Nationals Minor League players will be their first opponent.
Minor League Spring Training games are held on the backfields of Osceola County Stadium with a 1 p.m. ET start time. The backfields are only open to the public when the major league club has an away game and I'm assuming that means the public can only view games with the major league team out of town.
Here are the date and times of minor league games that should be open to the public:
AAA and AA
Thursday, March 14 vs Washington Nationals
Tuesday, March 19 vs Atlanta Braves
Saturday, March 23 vs Detroit Tigers
Wednesday, March 27 vs Washington Nationals
A+ and A
Saturday, March 16 vs Atlanta Braves
Thursday, March 21 vs Washington Nationals
Tuesday, March 26 vs Detroit Tigers
The Full Schedule