Well, some sources say that blueberries are safe after baby turns 6 months, some prefer to wait till they turn a year old. At least, here in Sweden (where I am currently living), babies are given blueberries (in the form of purees or unsweetened home made jams) as a complement to their oatmeal, yogurt or pancakes. If you are worried, you can try to give baby a little taste and gradually increase. Keep a lookout for any allergies or reactions. If you are wary, just wait till baby turns a year old.
http://www.livestrong.com/article/1002342-safe-baby-eat-blueberries/
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