"Playing in San Diego screwed me up. I'm not using that as an excuse or a crutch, but it turned me into a dead pull hitter. I got away from what I was as a hitter."
Using data available at FanGraphs:
2002-2009: 42.2% pulled balls in play
Ludwick spray charts, for the year before he was a Padre, and for the year that he was a Padre:
Ludwick might be on to something. The stuff above isn't broken down by ballpark. And it's possible that Petco did screw him up in a way he's not quite expressing. But at first glance, I think his explanation's a little simplistic.