|Berkheya purpurea flower|
I was first introduced to this plant about 10 years ago by the guys from Dancing Oaks Nursery. At that time, the plant was not very common here, but it seems to now be making its way into more nurseries here. I have found it at Swanson's Nursery in Seattle, one of the best retail nurseries in the Seattle area, and I have been able to special order it from my local retail nurseries. In a nursery pot the plant has nothing to distinguish it from any thistle--it is only when it blooms that you realise it is different.
In my front border this plant does very well, and it self sows readily. I can envision this making its way to a noxious weed list in the future. The noxious weed police seem to have something against thistle like plants.
I would not put this on the top of any list of great plants because the bloom period is not that long and the plant itself is not very distinguished looking. However, it is a useful plant for the deer resistant drought tolerant border or for wild areas of a garden.
Seed can be obtained from Silverhill Seeds and I notice that they have seven other kinds of Berkheyas, all of which should be hardy here according to their descriptions. None of the other ones have purple flowers, but they might be interesting to experiment with. I'm sure they are all easy from seed although I have not tried them yet.