Nick Maclaren wrote:
Blackberries are wood EDGE plants, actually, and don't crop in deep
shade.

Sure. But the fellow has full sun in the morning and late afternoon.

The problem is that there is a reaonable amount of light only from
early April to mid-September, and it is typically warm enough for
much growth in dark conditions only from June onwards. So essentially
nothing that needs to ripen fruit or establish foodstores (e.g. roots)
will grow well. Some foliage and similar plants will do OK in the
summer, and herbs don't need to make much growth.

What foliage plants do you have in mind? I didn't want to be too
negative - I've suggested rubarb, which I still find impossible to
spell for some strange reason. I've suggested quick growing crop, like
chicory and radishes which are happy in the shade, and in this case,
semi shade. But as for tomatoes, potatoes, sweetcorns etc ... frankly
it would be a waste of time.