Zone 5b you better hope for a warm winter. I think anything under - 20 c -5 f will snafu these trachy`s without some protection . Christmas lights, wrapping the trunk ,keeping moisture out of the spear ,using a fungicide will help spear fend off rot. How old are the Trachy`s? They will withstand colder temps as age and genetics, location in garden will determine what their limit is. Regards ,John
thanks for info , trachys are 3 yrs. old, this is first winter outside in a south protected exposure last few yrs. -18c is lowest will use chis. lites and will pray! john
This website has pics of four Trachycarpus fortunei in Bulgaria that were undamaged by -27.5°C in 1993 http://www.polarpalm.net/
Yes, trachies will live in Halifax(z6a or 6b in the southend) but you must protect them and site correctly(southside of a building)
Wow! Doesn't look like they get any protection at all on the website that Michael F linked. And here I am surrounding the container with layer after layer of polystyrene boards to keep the soil from freezing. I hear that it's the repeated freeze-thaw cycles that really do the damage for the spears.
Roots of plants are more tender than tops. Exposure to killing temperatures for only a short time is all that is needed to kill roots. My advice was for being sure of getting them through the whole winter undamaged, in above-ground containers.
