Last year we left the top of the summer fruiting raspberries and arched them over one another resulting in a very heavy topped plant which after a little bit of wind fell over. What do you when the tops reach the wire and when?
After fruiting, I cut out the fruited canes, tie in the new canes. I don't let them grow more than a foot above the top wire (about 1m80). Mainly because I'm quite small. :)
;D