West Midlands,
United Kingdom 
Hydrangea aspera
What is the best time of year to plant out a containerised (15L) Hygrangea aspera? Winter when dormant or now?
Have people found this to be a hardy species? The leaves are unlike others in the genus, much rougher and furry (hence "aspera").
26 Aug, 2015
You can do it now, if you're prepared to keep it well watered up to winter. Otherwise, early to mid October - again will need watering if we happen to have a mild, sunny one.
Its fully hardy down to -15 deg C
26 Aug, 2015