Gentiana andrewsii, commonly called Closed Gentian or Bottle Gentian, is a gorgeous, late-blooming garden treat. The petals of the beautiful blue flowers remain tightly closed, looking like large buds on the verge of bursting into full bloom.
This is a plant that likes relatively moist rich soil. This summer’s extremely dry weather was harder on my Closed Gentians than on most of my native plants, even with some supplemental watering. I worried that they wouldn’t flower this year. The tiny immature flower buds seemed to stay that way for weeks, although perhaps that is usually the case and I just hadn’t noticed. But I needn’t have worried. Even before the recent days of steady rain, the flowers seemed almost overnight to have grown and plumped up. The foliage is red-tinged rather than the deep green of previous years. But the rich blue of the flowers is stunning, and even more so on gray dreary days.
Closed Gentians are pollinated by bumble bees, said to be the only pollinators strong enough to force their way into the tops of the tightly closed flowers to get to the nectar. I was surprised when I first learned this, because most of the bumble bees I’ve seen on these plants have been on the outside facing down, clasping the base of the flower.
Just recently I just came across a link to a book, Bumble Bees of North America: An Identification Guide by Paul H. Williams, et al., with a fascinating observation. The authors note that bumble bee species with long tongues are better than short-tongued species at reaching nectar in long tubular flowers such as Closed Gentians. However, some short-tongued bumble bee species have learned to pierce the base of the Closed Gentian flower to get at the nectar. I have no idea if that’s what I’ve been observing. Maybe the bees are just resting after a difficult fight into the top of the flower! Please let me know if you have any knowledge or observations about this.
About the author:
Rachel Shaw focuses on vegetable gardening and growing native plants in her small yard in Rockville, MD. She blogs at http://hummingbirdway.blogspot.com/
This guest blog post is part of a monthly Native Plants series posted around the 10th of each month.