Posted: 18/01/2014 at 12:35
It is normal for roses to lose foliage over winter. In hard ones, mine lose them completely. Rambler roses flower on last season's wood so you should only prune it now to remove any dead or broken stems then tie in any which are flapping about and likely to get damaged by wind or interfere with passers by.
Formative pruning should be done after flowering to encourage new shoots and improve the shape. Here is what the RHS advises - http://apps.rhs.org.uk/advicesearch/profile.aspx?pid=169
Roses are hungry plants so I would also add a top dressing of dry rose food now and again in March. When watering, occasional liquid feeds with rose or tomato food up until June will also help with flowering.