Am I right in thinking that the Passiflora cultivars commonly sold with
'just' a Genus and Cultivar name such as Passiflora 'Constance Elliott'
and Passiflora 'Amythyst' 'Purple Rain' etc are in fact P. caerula
hybrid cultivars??

So should be pretty hardy?

I am getting quite a collection of Passiflora here;-)
//
Jim