wrote
Hiya, we have a front garden that points due north and consequently
most of it spends its life in constant shadow.
Now we know about hostas and ferns but can anyone tell us of anything
that is
(a) colourful,(b) perrenial,(c) low maintaince,and (d) shade loving,
snip

You could try:
Foxgloves (there are some perennials; the biennial ones will seed
generously around and replace themselves)
Primroses
Hellebore
Epimedium
Lamium maculatum
Dicentra spectabilis
Japanese anemone
Pulmonaria
Hydrangea
Mahonia
Skimmia japonica 'Rubella'

--
Sue