What direction do the banks face? Sunny or not sunny? Free draining poor soil? Acid or alkaline soil? How steep? And whereabouts in the UK are you? It could all make a difference to your choice of plants, Christine. Welcome to GoY!

Thanks! We are in the scottish borders,The bankings are all around the garden so some sunny,, some shady, not sure about acidity and most of them are quite steep, the children used to slide down them! and they made really good sledge runs in the winter!

Can you get a pH tester (quite cheap from garden centres) as if the acidity is suitable heathers would be good on the sunny side. Winter flowing heathers (ericas) would grow well in a less acid soil than the winter flowering callunas. A few potentillas in amongst would add a bit of height and give you colour earlier in the year and some of the hebes might be useful. You would need to make little mini terraces for then until established though to retain some moisture. Almeria might be OK too.
On the shady side you might try vinca - it does run wild but if that,s what you need then no problem
Sure lots of other suggestions will come along soon..

Thanks for your help,I'll pop to the garden centre in the morning for a ph tester!

I just had a thought. Does Kinnikinnick (Arctostaphyllos uva-ursi) grow in the UK?

Grows in rough scrubby woodland, I wouldn't recommend in a garden situation though.

One carpeting plant I'd recommend in this situation is Cotoneaster Queen of Carpets - evergreen or semi evergreen keeps creeping slowly, rooting as it goes, tiny flowers in spring, small berries autumn. Good in full sun, partial shade, not so good in complete,total shade.

Some varieties of kinnikinnick are used as soil binders and groundcovers in the western States, especially the Pacific Northwest, but it is something of an "area denial" plant.

What does 'area denial' plant mean, Tugbrethil?

Personally I'd go with Bamboo's suggestion we've got a horizontal Cotoneaster that has grown all the way across a gravel path, gets walked on regularly, always looks good and has to be pruned back when it starts trying to climb into the raised bed for our New Zealand alpines!

Having looked at the Arctostaphylos uvi whatever (which I'd never heard of) it might be just the ticket - it looks remarkably similar to the Cotoneaster I mentioned, just with prettier flowers.

Its common name is bear berry Bamboo and it grows readily in poor scrubby woodland near us - the individual bushes could well need pruning after a few years though which wont happen with the Cotoneaster.

Sorry, Bamboo! I've been off the net for some days. "Area denial" is a military term that I have adopted to refer to mass plantings and/or tall, wide groundcovers that keep everyone out--thieves, the homeless, the gardener, police, firefighters, the meter reader, etc. Such plantings can be useful along freeways, where they can brake an out-of-control vehicle, or as erosion control. Elsewhere, they just eat up garden space, for little decorative return.