Plants with flowers tend to like some light, but there are ferns and hostas which might help -you could grow then in pots or in the soil. Busy-Lizzies and bedding Begonias should give you some colour in the summer, though even those do get a bit 'leggy' in full shade...worth a try, though. Heucherellas are good in shade - they have great coloured leaves. There are a few hardy geraniums that don't mind shade, as well, which could be in the soil or in pots.

Try G. maculatum , G. macrorrhizum, G, phaeum, or G. nodusum. All these grow in shade.

Japanese Anemones should also be OK, Cimifuga aka Actaea, too. If you have room for a shrub , Mahonia species don't mind .they flower in winter so you'd get some colour then!

thanks tried busy lizzies and begonias but they just dont flower will try the japanese anemones is there anything on the market that will help create light eg light wells

I saw a wonderful display in a garden that was totally in shade due to a massive railway embankment, and if memory serves me right it only consisted of 3 types of plant; Buzzy Lizzies, Ivy and Hostas. All tolerate the shade very well and are also easily grown in containers. (as the word "yard" seems to imply would be necessary.)
However still too early in the year for that kind of display.....Spring bulbs in pots brighten a dark corner and I have an Aquiligia that grows well in the shade alongside a fern. Hope you find something you like.....obviously i'm a very slow at typing as there were no answers when I started typing but when I posted it there's already a little dialogue .....

Andy - I'm afraid I don't know about lighting, but there must be. Try a google!

If those bedders don't flower, then you may have to resort to ferns etc.

If you paint the walls white they will reflect what little light there is, you could also try affixing a large mirror to part of the wall.

gaia have a load of spring bulbs in pots my next door neighbour allows me to put them on her extension roof (this is a pain). spritzhenery any ideas on colourful ferns . and moon grower i have painted my walls white and and created mosaics out of mirrored glass but still to no avail :(

i have just found some aluminium funnels on a web site maybe i can tie it to my cherry blossom and create some kind of light well

You're certainly up for the challenge. What about mushrooms !!!! At least you could eat them :0)

The most colourful fern is Athyrium niponicum pictum. I'd try to stick to a variety of leaf colours as very little will flower in the 'dark'. You could rotate a couple of pots of summer flowers as suggested above. Keep one in the 'dark' and one in the light and swap every week or so. (Or buy some convincing fake flowers to stick in among the leafy plants!!)

There are lots of different leaf-shapes in ferns, Andy - they look terrific together. Take a look at some in members' gardens, and choose a selection. The one Volunteer suggested is indeed colourful, but it's also one that dies back in the autumn, and reappears in the spring. I'd imagine you want evergreen ones?
I have some in my garden in deep shade. I love them - and I have a driftwood sculpture amongst them, which I think looks good.

I've also got a wonderful cream and green stripy grass called Carex morrowii 'Ice Dance', which is in shadow all day - it thrives there! I recommend that to you.