All the Dirt on Gardening

North  Creek Nurseries Lavender Mist or Meadow Rue is a cold hardy (USDA zones 4 to 7) perennial that blooms in late spring. The reason they thrive only up to zone 7 is that they need a cold period to do well. About the rochebrunianum/rochebruneanum dichotomy in the title - The seed company I purchased them from as well as the new 2012 Sunset Western Garden Book uses rochebrunianum. Rob's Plants say that GRIN, the federal plant taxonomy site, uses rochebruneanum . The only reason to care is that when ordering seeds you might need to know. GRIN also says that this plant was discovered in Japan in 1878 and was named for a plant explorer, Alphonse Trémeau de Rochebrune (1834-1912). They are called Meadow Rue because they do best at the edge of a woody area in dappled light. Since they are not fond of wind, heat and humidity, their ability to be glorious in northeast Oklahoma remains to be seen. Our wind, heat and humidity are legendary. The reason I chose Thalictrum ...