Zynga’s FarmVille has more than 62 million monthly users on Facebook. And that has made it a magnet for marketing deals. The company announced that it has integrated special crops from organic food company Cascadian Farm into the FarmVille game.

Now, from July 19 to July 26, users will be able to plant organic Blueberries with the Cascadian Farm brand name. (Cascadian Farm is in the Upper Skagit Valley of Washington’s North Cascade mountains.) On top of that, players will benefit from coupon offers, organic and green living tips, and a chance to build a farm at high speed. For the week, the blueberries will be the most profitable crop a FarmVille user can plant in the game.   Users can “friend” farmer Joe Cascadian on Facebook.

The cool thing is that the advertising message here can be integrated into the game play without interrupting the user’s experience.

“When deciding on our first branded crop integration, we wanted to offer our users a unique opportunity that would benefit their gaming experience and add value to their lives both on and offline,” said Vish Makhijani, senior vice president of business operations, Zynga. Zynga also has a big partnership with 7-Eleven convenience stores, where Zynga-themed products and discounts can be found.

San Francisco-based Zynga has more than 215 million monthly active users.