Autumn Fruiting Raspberries

I grow quite a lot of autumn fruiting raspberries across one end of my allotment plot but the canes at the very end produce comparatively little fruit where my plot joins on to a neighbour's, whose own raspberries adjoin mine.  Conditions are no different where the plots meet and all my raspberries get a top dressing of well rotted manure and compost each year.  Can you tell me why the ones at the end produce hardly any fruit at all whilst all the rest are heavy croppers?  The canes otherwise look just as healthy.

Is there a path between your plot and your neighbour's?

Are your neighbour's canes fruiting well?

No path, and my neighbour's fruit well despite the fact that they receive no attention at all and are choked with stinging nettles most of the time.  Where the stingers intrude into my plot I get rid of them each year.

Funny thing is - nettles mean rich soil.  Perhaps your neighbour has richer soil than you do!

That's what I was thinking. Odd that the difference in Mary's patch is that small intersecting area, though.