What can be planted on a shady, damp slope to help remove weeds?

Question

I am removing ferns and brambles from a steep, damp and shaded hillside. Proper planting will come later but first I want to have some ground cover that will help keep the weeds from re-establishing and help lock the slope.

I am in mid-Wales (United Kingdom) so summer temperatures are 15-20C (59-68F) and winters can easily hit -5C (23F)

I have considered Phacelia, which is quite a good green manure, but wasn't too sure if it would thrive.

Answer 1

I suggest you try ivy; it will take some time to become established, but thrives in the most adverse conditions and forms excellent ground cover. I have used it beneath some mature Leylandii trees, where the soil is extremely dry and nothing else will grow, and it is still spreading..

Answer 2

I'm only quoting a notcutts book here: Bergenia, caltha, Cornus canadensis, Cotoneaster low growing forms, Leucothoe, Pulmonaria, Rubus calcycinoides/tricolor, Waldsteiner. Also:
Ferns, Gaulteria procumbens, Hedera colchia/hibernica, Helleborus, Hosta, Pachysandra terminalis,Pernettya, Polygonum, Rhododendron, Rubus cockburnianus/thibetanus/tricolor, Ruscus aculeatus, Sarcococca humilis, Spiraea thunbergii/x vanhouttei, Symphoricarpos? wouldn't advise that one, Vibrnum davidii and Vinca. Although I have seen for geolocking ground on a steep slope- the professionals use willow? not good for ground cover but its roots are good for making matrices for holding back unstable rocky slopes near motorways- hope it helps.

Answer 3

Ivy seems an odd suggestion on the basis that it has proved to grow well where the soil is extremely dry, given the inclusion of damp slope in the Title. Hedera helix (there are other ivies) can make a nuisance of itself in many settings but it does prefer the soil it lives in to be well-drained.

However Phacelia may be an even stranger suggestion if the question is anything like my interpretation of the requirement. For Phacelia GrowVeg recommends:

Soil
Any sunny site with good drainage.
Position
Full sun to partial afternoon shade.
Frost tolerant
Phacelia seedlings can tolerate light frost, but the plants are easily damaged by hard freezes.

"shaded hillside" and "can easily hit -5C" are at odds with the above.

The (rather limited) conditions mentioned by OP include shade, moist and ground cover and selecting "Sunlight: Partial", "Moisture: Moist but well-drained", "Planting places: "Banks and Slopes", "Hardiness: H3", "Habit: Mat forming" and "Native to the United Kingdom" at the Royal Horticultural Society plant selection site, returns only one result, Fuchsia procumbens. Although the OP has not mentioned soil type or pH, this plant can be comfortable in Sand, Chalk, Loam, Clay whether Acid, Alkaline or Neutral (RHS).

Other details that might have helped are aspect, exposure and time scale. For "lock the soil" it might have to be a case of choosing priorities - plants that provide ground cover quickly generally have shallow roots.