that kind of harder pruning is best done last week of February or first week of March, depending on the weather; that is the time to prune HT, climbing and floribunda roses, when you'd normally remove any damaged, dead, diseased, weak or crossing stems to improve air flow to the rose. Cut back to outward facing growth buds using sharp, clean secateurs or loppers for thicker stems, making a slightly angled, clean cut facing down from the growth bud to allow rain to run off They also benefit from application of a specialist rose food such as Toprose in mid April, with a second application 6 weeks later; also mulching with composted manure or good garden compost in April/early May, onto damp soil.