I transferred some small rasperberry canes in the Summer ( and I use that phrase loosley ) and they are now just 3 foot high having fruited sucessfully
? When do I prune them if at all please
Are they summer or autumn fruiting type?
Only been an alotmenteer for a year so how do I tell ?
Ok Where did you get them from, did they have a label or a variety name, or were they on the allotment when you took it over?
If we don't know anything else about them, when did they fruit?
I dug them up from where I placed my home made composter and I just moved them into a straight line about 6 foot away
They fruited @ in August / October or possioble a bit earlier
My guess is that they're an autumn fruiting variety (as you say they're not overly tall they may well be Autumn Bliss). They fruit on canes produced earlier in the same year and they're simple to prune as you just cut them back to a shoot near/at ground level as soon as they've fnished fruiting. It's a little late to do it now but no matter, cut them back and mulch with some compost and new shoots will appear in the spring and bear fruit for you in the autumn.
If by any chance they are summer fruiting then the old canes should've been cut out after fruiting and the new canes that were already growing should've been tied in to grow on through the autumn - they will bear fruit next summer. If they are summer fruiting cutting them back now will lose your next summer's crop, but from your description I'm pretty sure they're autumn fruiting.
As usual a proper answer
Slightly disagree that it is a bit late to cut down autumn fruiters; we usually do ours in February.
If they are summer fruiting will there not be new canes already growing up? In which case only the fruited canes should be cut out. Though newly planted summer fruiters should be cut down after planting so that they can establish well before they fruit for the first time in 2014. This is of course a counsel of perfection; most people don't wait for a year before cropping.
If you're not sure which variety they are, the easiest way to deal with them is to cut the canes to ground level immediately after fruiting, or as soon as possible after. Many 'Autumn' varieties can be grown as either Summer or Autumn fruiting and as long as you only cut the canes that have fruited down, you'll get a crop from the remaining canes. The thing to remember is that canes which have already fruited will rarely fruit again (and if they do, the crop from them will be small.) Cutting fruited canes back encourages new shoots and the more of those you have which are strong and healthy, the more fruit you'll get. If you leave unfruited but old "Autumn fruiting" canes alone, they will act like early Summer fruiting canes next year.
Well yes, I agree with Welsh Onion, as long as autumn fruiters are cut down before growth starts again in the spring that's fine.
And yes again, as I said, if they are summer fruiting then there should be new canes already growing up and I'd hope that they'd be taller than the 3ft NewBoy described, so my suggestion is to go with the assumption that they're autumn fruiters.
If they are summer fruiters he'd be able to tell the old canes from the new by the evidence of the old shoots that bore the fruits this year. But I didn't want to complicate matters - it does sound to me as if he's got autumn fruiting raspberry canes there.