I agree; the canes are too old. It is not a problem with building
debris.

Mel wrote:
My new allotment was dug up by the council with a massive digger, so there's
lots of debris (boulders, wood boards, etc) buried in the soil. The soil is
very heavy and wet.

Last weekend I started to dig out a trench for raspberries, and holes for
red/white/blackcurrants. After about 1 or 2 spits deep, more often than not
I hit rubbish that took herculean efforts to dig out, and very soon my back
gave up.

I'd planned to dig 2 spits deep and then add manure to the trench. If
there's debris at the 2 spits depth, is it okay to leave it there and hope
the roots find their way around, or does it all have to come out?

Thanks.