CINCINNATI (Reuters) - The Cincinnati Reds stretched their unbeaten start to the season to five games with a 12-4 blowout over the Houston Astros Wednesday.

It is the first time the Reds have started a season 5-0 since 1990, when they last won the World Series.

Houston roughed up Cincinnati starter Edinson Volquez in the first inning, sending 10 batters to the plate and scoring four runs.

Cincinnati responded with a run in the second inning and grabbed the lead in the third, capitalizing on two Houston errors to score five runs.

The Reds added four more runs in the sixth inning and two in the eighth as the Astros made three more errors.

Volquez survived the rough start to pick up his first win pitching five innings, striking out eight, walking five and allowing four runs on five hits.

"I just have to be more careful in the first inning," said Volquez. "After that, everything worked. I threw more strikes. I kept the ball down and the breaking pitch was there."

Nelson Figueroa allowed 10 runs, six earned, while striking out two and walking one in 5-1/3 innings for the loss.

"It's tough against a team like that," said Figueroa.

"Once they get the momentum going, it's hard to stop.

"They were stringing hits together and making the most of the mistakes we made.

"They seem to take advantage of every mistake you make. It's a testament to the way they played last year and so far this year."

(Reporting by Mike Mouat in Windsor, Ontario. Editing by Alastair Himmer/Greg Stutchbury)