Cut them back to about 5 foot now, it wont do them any harm.

An alternative is to cut them right down to their base, and enjoy later longer fruiting summer/autumn raspberries. Whichever you choose, don't forget to give them a good feed when they start flowering - top rose is good for raspberries.

Avkq there are summer fruiting raspberries and autumn fruiting ones. Summer ones you cut the canes back in early autumn, cutting back to 5 foot, or so as late as it is this will still work. Autumn fruiting canes you cut back to 6 inches in February, early March. However, if you do this to summer fruiting canes you will get no fruit this year.

You could cut out the canes that fruited last year, now, but separating them from the new ones--which you want to keep--is a nasty, scratchy, impractical mess! I would be tempted to let them all go, and chop it all back right after fruiting this summer.

I should have said you 'ought' to cut out the canes that fruited last year - thanks TugB. Though as you say at this late date it is going to be difficult to tell which is which, done just after fruiting it is obvious. So this August/September cut down all the existing canes Amanda and trim the new canes to around 5 foot.

Thank you, MG. I do know about summer and autumn raspberries! I once made the same mistake as amanda, however, and cut them down to about a foot in the winter, and had a good crop later than normal for summer raspberries but before the autumn ones. I kept them sheeted with polythene until the spring, then well fed and well watered and the mistake for one year was corrected.