Tricky spot, looking for groundcover

(Question)

I’ve read your main article on evergreen groundcover, which has been helpful. However, I’m having a hard time narrowing my choices to a plant that meets all my needs.

I have a spot in my front garden that’s 80% shaded, rocky clay, shallow, and dry as a bone. Heather and ferns have died there. I was about to give in and get ivy, but do want to avoid invasives.

Do you have two or three suggestions for an evergreen groundcover no more than 10 inches high, that can survive in this trouble spot? Thanks!

(Answer)

Thank you for using our Gardening Guide on Evergreen Ground Cover and then for your follow up question . A wise gardener once said that dry shade is potential to be fulfilled , not a problem to be overcome . Let’s see if we can work on that. And don’t be discouraged that ferns and heather didn’t survive..some ferns are easily killed and both of these plants like moisture which you do not have .

Before thinking about plants, could we consider a few other ideas? Would you be happy with an area of shredded leaf mulch? Some very elegant Toronto gardens have this feature (but you would want to be sure the area is not exposed to the wind or leaf blowers that might blow the mulch away). What about fine gravel or stone which gives a gracious calm effect ? You could put a bird bath, water feature or pots of annual shade plants there. Have you tried amending the soil? (Clay actually contains many nutrients if only the plants could get their roots into it.)

I can’t get a sense of why the area is so shady. If trees, could they be trimmed? Or the extent of the area (could it be repurposed into a sitting area with stone or wooden decking with perhaps a nice pergola overhead with a vine to soften it ? What about a rock garden or other xeriscaping?

Some plant suggestions: While we do not usually suggest aggressive plants , in your garden conditions, it is doubtful that anything will thrive so well that it will become aggressive and  escape so some of these suggestions rely on that risk assessment but please don’t be casual about this, especially if you live near a park or natural space . You must keep an eye out and control it, perhaps using a barrier like raised beds, stone or brick edges .
These are not evergreen but they suit your height requirements and, assuming you can get them into the clay at all , with some compost ,then water until established, their short roots or rhizomes make them good options: of all of these, Big-root geranium (Geranium macrorrhizum) might suit best because its roots are so shallow that the plant practically skims the soil surface, making it easy to remove if you don’t like it (an added advantage is that dogs don’t like it. A disadvantage is that it has a fairly strong odour).

Others to consider:  barrenwort( Epimedium, especially the Mediterranean varieties) , sweet woodruff (Gallium odoratum) (in fact, if happy, sweet woodruff gets aggressive ,so in your adverse conditions this might be a nice solution ..it is green and voluminous all season, has pretty white spring flowers and a nice scent that moths do not like ..I dry mine and use it in my sweater drawers) ,  wild ginger ( Asarum canadence),wild strawberry(Fragaria spp) . While Virginia Creeper( Parthenocissus quinquefolia or P. vitacea) has fallen out of style , it is a hardy native plant that pollinators love, has nice texture and colour and I have seen used to good effect both as a ground cover and climbing a structure. Again, warnings about aggressive spreading .
Most sedges do well in dry shade . Many are evergreen, shade and drought tolerant (once established some even adapt to clay), spread but not aggressively and all add movement . An example might be Ebony sedge (Carex eburnea), found in limestone cracks and tolerates shade,spreads slowly by rhizomes to form a soft textured groundcover but needs moisture until established. Japanese sedges (Carex oshimensis ‘Everglow’, ‘Everlime’ and ‘Evergold’) might also suit and brighten up a shady space.
Evergreens that suit dry shade but would need some compost and water until established:  bergenia  (Bergenia cordifolia), creeping juniper (Juniperus horizontalis), rock cotoneaster (C. horizontalis) but these latter two might be too tall for you as they mature around 2 feet. Plants from the Cupressaceae family are some of the worlds’ toughest. Most need sun but some (like Siberian cypress) will tolerate shade and actually like dry conditions, once established.

Whatever you choose, try combining plants for the sake of biodiversity( in case one dies , the other(s) might still be all right) and for the sake of texture (different heights, textures and colours helps to break up a monotonous visual mass of the same plant). Think of the fun you would have exercising your creativity.

Hopefully , this will give you some direction if not immediate simple solutions. Please try to have fun cruising nurseries and investigating some of these possibilities and please feel free to continue the conversation by writing back , if you want to talk about specifics. Thank you for contacting Toronto Master Gardeners .