Pictures can't capture just how blue the flowers are on Bottle Gentian (Gentiana andrewsii). Bottle gentian is native to Wisconsin, where it is often found in swampy, wet areas. It grows in full sun to partial shade, which makes it great to add a pop of color to any garden. Unlike the balloon flower or hosta flowers, these flowers never open. Bumblebees are one of the few insects that can find it's way inside of the flower to collect pollen.