Get festive and embrace the luck of the Irish while displaying your team pride with St. Louis Cardinals St. Patrick's Day clothing and gear from MLB Shop! Browse a great selection of green Cardinals |shirts, hats, sweatshirtsSt. Louis Cardinals St. Patty's Day merchandise. Snag a new Cardinals St. Patrick's Day jersey in Kelly green featuring your team's official graphics for a festive look while you support your team this St. Patrick's Day. Go more casual with a trendy green Cardinals St. Patty's Day shirt to join in on the festivities in style. Complete the look with this year's St. Louis Cardinals St. Patrick's Day hats and accessories. We have everything you need to show off your team spirit this St. Patrick's Day at MLBShop.com.