A few years ago I visited a rose garden. It was the type of rose garden I really like: All sort of roses were the star performers, but there were plenty of companions plants too. Hardy geraniums, many other perennials, annuals and bi-annuals. Among some of the roses I noticed one of the most intense blue flowers I had ever seen. She did not know the name of the plant - she had bought it at the local flower market a few years ago, and to her surprise it had selfseeded.
I did some research and found that the name of the plant was Salvia Patens. Or Gentian Sage - a fitting name for the gentian blue flowers. It was different from other salvias I knew - it did not have as many flowers on the flower stalks and they were much bigger. I harvested some seeds from her plants and next spring in April I sowed some in my mixed borders. In late July the 2 feet tall flower stalks began flowering, putting out the most intense blue flowers. In USDA zones 8 and higher these plants are hardy and like dahlias, produces tuberous roots. Since I live in a colder climate zone I learned that the tuberous roots could be dug up and stored frostfree like dahlia bulbs. Planted again in mid April they would flower in June. Since I also sow some seeds every year I can have these intense blue flowers 3 months every season, from both the tuberous bulbs and later again from seeds. I really appreciate them in august and September when many perennials are beginning to look a little tired.