Everyone knows Carrie Underwood slays when she’s onstage — she’s one of the biggest stars of the last 20 years across genres — but she’s an expert in other areas, too. Underwood has one of, if not the best, green thumbs in country music. The “Blown Away” hitmaker loves showing off her growths and harvests right from her backyard. On Tuesday (July 30), Underwood was proudly sharing her huge melons with fans. The singer posted a variety of large melon photos on her Instagram Story, including a massive honeydew larger than her head. This bad boy was grown with love and care for sure, as it looks …