please help with north facing shaded garden: want flowery idyll in spring

[funnyperson]

I am struggling with my small north facing back garden , shadowed at one end by the house and at the other by a magnificent large old oak tree with a preservation order on it. The beds are on three sides.
None of the summer perennials flower- japanese anemones, blue geraniums,lacy hydrangeas: the spring is nice, with winter jasmine, hellebores, snowdrops, crocuses and forget me nots before the oak tree leafs up. Clematis doesn't flower not even the montana species, not even sweet peas. What can I do with the side beds for a flowery and fruitful summer and Autumn next year? All advice really appreciated

And how can I help the japanese anemones to flower this year - is it too late?

Alo, do people put in special soil for the magnolia/azalea/rhodedendron effect?
Do people have a separate bed for them? Or is it best to have them in pots?

sorry-also

dont know if this is too late but taken from bbc website
Many spring-flowering bulbs are ideal for brightening up the base of trees before they come into full leaf. The soil beneath trees is moist and light, offering the perfect growing conditions for scillas, anemones, erythroniums and crocuses.

Bulbs such as dwarf daffodils, crocuses, snowdrops and winter aconites can transform a dull looking lawn into a wonderful display of colour. To achieve a natural look, throw bulbs up in the air and plant them exactly where they land in the grass. The aim is to make it look as though they have decided to grow there by themselves. Allow plants to die down after flowering before mowing over the lawn. Alternatively, plant bulbs in defined areas so that it's possible to mow the lawn around them.

watching for inspiration as similar situation. some philadelphus do really well in my garden - one with lemon coloured leaves, says they like dappled shade. other shrub that flowers in darkest corner is chosia - mexican orange blossom. obviously periwinkle and kerria. sweet peas need loads of sun, but if you've only just planted the other things i'd leave them a few years and see what happens. i have some of yours and they do flower in shade.

you prob have acidic soil, so don't need to do anything special for azaleas etc

My front garden is like this, luckily I got a blank canvas after our extension when a skip had been left on it for 9 months!
In spring, I have "bleeding heart/dutchman's breeches", hyacinths, flowering currant, snowdrops, daffodils, crocuses, astilbe, foxgloves, Arum, London pride, cornflowers, irises and Alliums.
I grew most of them from seed or cuttings from other people's gardens.

Ferns like shade too, we have a big fern!

Thank you: I invested in some snowdrops, crocus species, anemone blanda and fritillaria; am thinking about an azalea and perhaps rhodedendron.

Do the astilbe, foxgloves and irises flower in the shade?

On another thread someone mentioned a good fragrant red rose for shade so I might plant that, and I will move the sweet peas , cistus and some of the Johnson's blue geraniums to the south facing front garden!

All the ones I mentioned flowered in the shadiest bit of the garden, direct sunlight for about an hour a day but only in the height of summer.

Don't get rhododendron ponticum though, it leeches poisons into the soil so nothing else will grow there!