A few people here in the San Francisco Bay Area are growing this in areas that regularly get killing frosts, where it has survived 22F and returned from the roots, with mulching. However, the winter lows of this magnitude are of rather short duration, and the hot summer weather in places like Danville, Ca. help harden it off so that it can act as a herbaceous perennial. It is much safer to grow this in frost free areas,(it is evergreen for me here in Berkeley, Ca. where we typically only get light frosts, if at all). It does flower best with full sun and summer heat, being somewhat shy to bloom in the fog belt coastal areas here, and tends to drop all its leaves in winter if it hovers in the high 30'sF.

Here, near Houston, the plants do well. They take a surprising amount of cold and spring back the next year. They seem to enjoy the humid heat. One report in our Texas Garden Forum claims they are root hardy in North Texas, zone 7/8.

On Galveston Island, where there is seldom frost, the plants get tremendous, at least 12 feet tall. There seem to be a number of selected forms, some taller, some shorter, some more blue, etc.

It is a very easy plant to root from green wood, even in water as long as you change it nearly every day.

One other note, I don't fertilize mine; someone reported to me that fertilizer stimulated the plant to grow and grow, but flowering was much delayed.

Cordially,

Getting them home, I had thought from examining them that they would be relatively easy to propagate. (Lots of nubbies on the wood and green wood at the tops of non-blooming branches.) So I will be trying that fairly soon. Want to trade for a few, if I am successful?

Just a note here to say I rooted my plants in a glass of water, it took about 3 weeks and I changed the water daily. They indeed do seem easy to root.

Cordially,

Thanks,
Chris