Cold hardiness of hybrid witch hazels
I am wondering who out there has grown any of the hybrid witch hazels like Arnold's Promise, Jelena, Diane etc. in zone 5 or colder zones. How about chinese witch hazel Pallida? Whats the upper limit on cold hardiness you have found.
Lots of sources say 5 or 6. Any success in 4b?
Here is a link that might be useful: Witch hazel tree for flowers in February