Their Facebook doesn't work anymore, so you might try googling it. They don't have an active website. Try http://www.kansastravel.org/lawrence/grinterssunflowerfarm.htm
Their Facebook page is always updated with sunflower status.
You will have to go to their website and they will keep you posted on when they are blooming. In past years it has been in August and September.
Thanks everyone!
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