Manager Kirk Gibson said he hopes his team can continue to exhibit consistency on its upcoming 10-game homestand. The first seven games of the homestand are against clubs with losing records.
"I think we've got a real good feeling about ourselves," Gibson said.
Hill hit two homers, his second and third since Saturday. It was Hill's fifth career two-homer game. He also hit two homers on April 7 against the Giants.
Hill started off the fourth with a solo shot to the left-field boxes off Armando Galarraga. Jason Kubel and Paul Goldschmidt followed with singles. Chris Young scored Kubel with a single. Goldschmidt and Young moved up a base on a double steal and Goldschmidt came home on a bases-loaded walk to Stephen Drew.
Young scored on Kennedy's sacrifice fly to left field and Drew raced home on Gerardo Parra's two-out double to center field, giving the D-backs a 5-0 lead.
Young, born in Houston, finished 2-for-5 and moved his average in 16 games at Minute Maid Park to .418. He finished the series 7-for-14 at the plate.
"I'll try to take as much as possible [from this series]," Young said. "Take all the good at-bats here and just try to carry them over and finish out the season strong."
In the eighth, Hill hit his second homer of game, taking reliever Fernando Rodriguez deep into the left-field boxes with nobody on base. Hill fell behind in the count, 0-2, but worked eight more pitches out of the at-bat and homered on the 11th offering from Rodriguez.
The D-backs scored 56 runs against the Astros this season and allowed 19.
Kennedy picked up his 11th win, but walked a season-high five batters in his six innings. He left runners on base in five of his six frames, only recording a clean third inning. Seven strikeouts helped Kennedy escape a few sticky situations.
"That's what I really take pride in -- not walking too many guys," Kennedy said. "Thankfully, we hit well today. I put a lot of hitters in hitters' counts and just luckily got out of it."
Kennedy hadn't walked more than three batters in a start all season. The last time he issued five or more walks was June 26, 2010, when he walked nine.
Astros catcher Jason Castro said Kennedy's rising fastball caught a lot of the team's hitters off guard.
"You have to give credit to him," Castro said. "He did a great job, kind of pitching in some big spots where he needed to get outs."
Fernando Martinez nearly hit a solo homer to lead off the Astros' fourth, lining a ball high up the wall in left-center field. The umpires originally ruled that the ball hit above the yellow line on the outfield wall. Gibson argued the call, so the umpires went to video review, determined the ball had stayed in play and sent Martinez back to second with a double.
Martinez moved to third on a flyout to right field, but was stranded.
Tyler Greene led off the sixth with a double and came home after a 4-3 double play and an RBI single by Castro.
Reliever Matt Albers, who played with the Astros for two seasons, struck out the side in the seventh. His ERA in his last 19 games (15 2/3 innings) is 0.57. He hasn't given up an earned run in seven appearances as a D-back.
Bryan Shaw tossed a scoreless eighth with two strikeouts and Mike Zagurski stranded two runners in the ninth.
The D-backs have had five stretches of four wins or more in a row but have also endured more than a few losing streaks. Hill recognized the team's lack of consistency.
"But it's never too late," Hill said. "We know we have it in us."