Following some works in our front yard, we are left with a very steep slope. The soil is quite sandy, so the builder suggested to add some plants to help stabilise the slope:
We live in the French Alps. The slope has a south-east exposition but is partially covered by the house.
I would like some plants that keep the foliage in winter
First plant I can think of is creeping thyme. It's low growing, it will root all around and thus help stabilise the slope, once implanted it's dry tolerant, it smells good, can be used in the kitchen and insects will love the flowers :)
We're also getting close to the season when you can just walk around and start gathering seeds from wild flowers around you, which would surely be well suited to grow there.
Quelle chance de vivre dans les Alpes !
Vinca minor (I know it as creeping myrtle; apparently lesser periwinkle is a more common common name) is a short evergreen groundcover; it's considered invasive in some areas.
Vaccinium vitis-idaea (Lignonberry) is a more useful-to-humans short evergreen plant, due to the berries.
Lowbush blueberries are not evergreen, but have nice foliage colors in the fall and similarly useful-to-humans berries. Vaccinium myrtillus known as bilberry would be more native to your area.
Vaccinium oxycoccos is a cranberry that's native to Europe and evergreen, but it may find the conditions on your slope too dry.
Gaultheria procumbens Checkerberry or American Wintergreen is another low-growing evergreen with berries useful-to-humans, but does seem to be lacking a direct Euopean counterpart, so it might be hard to come by. Does like a sandy slope, in my experience.
Juniper is available in forms from trees to low-spreading shrubs.
You didn't really specify short plants, those are just what springs to mind first for covering a slope. In a taller plant, Azeleas are available evergreen or not, and like well drained soils.
Take a look at Rubus tricolor and Hedera helix. Both are vigorous ground coverers.
