Shade Ground Cover for Septic Bed


We have a cottage north of Parry Sound. Originally grass was seeded over the septic bed but it has long since disappeared and I pull out little tree seedlings that sprout out every fall. I tried scattering wild flower seeds last fall but they didn’t take. The area is more shady than sunny but does get mottled sunlight. What would be a good ground cover? I thought of ajuga, Lily of the valley, ferns. It is a large area about 7×12 metres so cost and availability of plants/seeds are a consideration. Transplanting native plants from our 4 acre property is a possibility. Any suggestions would be greatly appreciated. The photos that I have are too large to attach. I’m hoping you have enough info to go on. If not, I will try cropping the photos if I can. Thanks!


Thank you for contacting the Toronto Master Gardeners.

I applaud your decision in replacing your high-maintenance turf with ground covers. By removing your grass you not only reduce the need for irrigation, but stop the addition of harmful chemicals into the watershed. In turn you will add depth and texture to your landscape and spend more time enjoying your yard instead of trying to maintain your lawn.

There’s a ground cover to meet most needs, they run the gamut of foliage textures and colors, and many have wonderful flowers. Some varieties are ground-hugging, others grow up to two feet tall, adding depth to your landscape.

Adding a shallow layer (about an inch thick) of organic compost over the area that you would like to cover with plants will ensure your new plants will have a supply of nutrients to reach out for. The compost will also trap valuable moisture. Check this compost layer each spring and top up as necessary.

Here are a few perennial ground covers which can tolerate lower light conditions. Depending on your soil type, you may like to research the following possible plant choices:

Canadian Snakeroot aka Wild Ginger (Asarum canadense): spreads slowly and is low growing (height about 6″ -12″) . It has nice downy, heart shaped leaves and brown flowers that are hidden under the leaves

Carpet Bugle (Ajuga reptans): 

Bunchberry (Canadas National Flower) (Cornus canadensis): This plant grows 5-15cm tall and produces white flowers followed by red berries.

Foamflower, (Tiarella cordifolia): has 3-5 lobed leaves that make a pretty ground cover and the fluffy white flowers on long stems are a welcome sight in May

Cranesbill Geranium, (Geranium maculatum): Grows in sun to part shade in medium-moist soil. Flowers pink in late-spring and early-summer. This plant has the added bonus of being a nectar source for hummingbirds.

Sweet woodruff (Galium odoratum) is one possibility – it is a very pretty plant with white flowers in spring and its leaves are scented (hence its Latin name).   Another plant that lightens up a bed is  Japanese Forest Grass, Hakone macra ‘Aureola’

Barrenwort (Epimedium) species and cultivars come with different attractive leaves and flower colours. Epimediums grow 8-15″ tall and have very delicate leaves and flowers.

Christmas fern (Polystichum acrostichoides): This plant requires cool, moist, well-drained soil in shade.

Lily of the Valley (Convallaria majalis) is an effective groundcover because it spreads by a vigorous networks of rhizomes in addition to seed. The plant does have its drawbacks, it is toxic to animals and humans and has the reputation for being an invasive species.

Happy planting!