This plant is on the invasive plant list in most of North America and it is actually prohibited in Colorado. Ironically enough I got this plant from the Denver Botanic Garden. It is an easy plant to grow as you can imagine and very popular with insects. The flowers dry well. It is drought tolerant which is a big plus this summer. August here was a record setting month and so far, September continues in the upper 90s. Usually at this time of year I revive the lawn but this year it is completely parched.