Simmons missed the first week of spring games because of an oblique strain. The shortstop is 5 for 9 in three games since his return to the lineup.
Veteran left-hander Wandy Rodriguez, bidding for a spot in the Braves' rotation, allowed two hits over four scoreless innings. He walked three and struck out two while lowering his ERA to 1.13 in three starts.
After hitting a pair of RBI singles, Simmons homered off Tony Sipp in the fifth.
Colby Rasmus and Brett Phillips homered for Houston.
Collin McHugh, who led all rookie starters with a 2.79 ERA last season, gave up five runs in 2 1-3 innings for Houston. He hadn't given up a run in his first two spring outings.