A temperature of 35- 40 F.(2-3.C.) should be sufficient to keep plants alive over winter.
It is essential that the plants be kept frost free and never be allowed to dry out.
Prior to storing defoliate plants by hand if they have not done this naturally.
To start the new seasons growth spray with tepid water as soon as conditions allow.
In early Jan/Feb if heat is available or late Feb/March if not.
Cuttings can be taken at any time in the growing season, but best results are achieved with softwood cuttings i.e. early season growth, taken in May /June.
Hardwood cuttings taken in Autumn take much longer to root
Select a cutting 50-70mm(2"-3")long,remove all the bottom leaves leaving the top pair and tip. Trim stem to just below a leaf joint/node. Insert cutting into a pot/tray containing a mixture of peat and horticultural sand (50-50 by volume)
Water the cuttings in well and place in a shaded propagator holding a temperature of around 12 C (55/60F).
Cuttings should never be allowed to dry out, Spray them regularly with clean water
(depending upon the growing conditions )
Cuttings should root in about 12-14 days.
Note The above instructions should give the novice a fair degree of success,improved results will come with experience