By Snoopdog
shropshire,
United Kingdom 
advice on rose bush please this bush has large yellow flowers and they will flower until frost,it is getting on a few years now and there are many stalks?growing to make the bush.but it is now looking a little fat ,would it maybe a benefit to prune it down about 12"also ?would it come to harm if i cut some of the stalks out there are two new ones grown as high as the bush i add that it is srongly scented beutiful on a warm afternoon
23 Aug, 2013
Answers
Early March is the time a lot of people prune roses. If its done now there is a danger that new shoots will grow and not have time to ripen so they will be killed by the frosts.
23 Aug, 2013
Agree with both responses above. You can risk doing it when the plant is dormant in winter though, but I'd do it last week of February, unless you live in a cold part of the country, when March would be better.
23 Aug, 2013
Avoid pruning to inward facing buds or it will get congested again.
24 Aug, 2013
It's a pleasure - I'll be driving people nuts with my questions so more than happy to offer my two penn'orth of help where I can.
25 Aug, 2013
Previous question
It does look a little congested. I'd be inclined to go for the cutting out 1/3 of the stems pruning option.
RHS advice:
To start with, cut out dead, diseased, rubbing and crossing stems. If the bush is crowded cut out some old shoots completely to keep the centre open.
Then proceed as for hybrid tea or floribunda roses, as follows:
Hybrid tea (large-flowered)
Shorten back the strongest remaining shoots to four to six buds 10-15cm (4-6in) from the base, to the point where last year’s growth began.
Shorten back less vigorous shoots to two to four buds 5-10cm (2-4in) from the base.
At Wisley the aim is to cut out all three year old wood, leaving only younger more vigorous growths, which produce better flowers.
23 Aug, 2013