Ground Covering Plants for Ottawa-Carleton

There are many alternatives to grass if you want to cover ground with a single kind of plant, especially in shady areas. Here are some of the best.

• Thyme (Thymus montanus or T. serphyllum) A cover for full sun and dry sandy soil, especially useful between patio stones, leaves scented, has tiny flowers late spring, several good varieties.
• Ajuga (Ajuga reptans) A fast-spreading ground cover, sun to light shade and moist soil, 10 cm high, spikes of deep blue flowers in late spring over shiny rosettes of leaves, multi-coloured leaf cultivars available. 'Braunherz' is especially resistant to insect attacks.
• Sweet Woodruff (Galium odoratum) Best in moist shady spots where grass won't grow, whorled green foliage, tiny white flowers in spring.
• Lily-of-the-valley (Convallaria majalis) Thick-growing upright leaves 10 cm high, suppresses almost all other plants if grown in moist soil and medium to deep shade, fragrant flowers in spring. The bright-orange berries in summer are sufficiently poisonous that children should be prevented from eating them.
• Periwinkle (Vinca minor) Medium to dark shade, 15 cm high with shiny green leaves, many blue flowers in spring, withstands drought once established but young plants must be watered, some weeding required.
• Goutweed (Ægopodium podagraria) Sun to medium shade, spreads very rapidly (even invasively) by underground roots, cream-coloured leaves, 15 cm high. Control by mowing along edge of patch three times a year.
• Japanese spurge (Pachysandra terminalis) Best in light to dark shade and well-drained soil, 15 cm high, some have variegated leaves, excellent to combine with bulb plantings to hide the ripening bulb leaves after flowering. Control by mowing.
• Creeping phlox (Phlox stolonifera) Forms dense clumps of spreading stems, many small blue, pink or white flowers in spring, best in light to medium shade such as under trees, moist soil. Phlox subulata, also called creeping phlox, forms a moss-like mat 15 cm thick with flowers in early spring, needs full sun, well-drained soil, and some weeding, the middle of large plantings tends to die off.
• Creeping juniper (Juniperus horizontalis) Grows slowly, but excellent for covering rocky slopes, requires full sun, dry even rocky soil, good air circulation. Cultivars available for heights from 20 cm ('Wiltonii') to 60 cm.
• Three-toothed cinquefoil (Potentilla tridentata) A creeper for rocky sites and dry sunny slopes, 25 cm high, small white flowers early summer, leaves turn reddish in fall.
• Foam flower (Tiarella cordifolia) Grows 25 cm tall in medium to heavy shade and rich moist soil, white flower spikes in spring.
• Crown vetch (Coronilla varia) The cover for sunny banks that are too dry for grass, forms an intertwined mass up to 30 cm thick, flowers all summer.

See our separate information sheet on Ecological Lawn Care. We thank Artistic Landscape Designs Ltd. for expert assistance in compiling this fact sheet.

Provided by the Health Dangers of Urban Use of Pesticides Working Group of the Region of Ottawa-Carleton, Ontario Canada. Approved by Regional government and by the Ottawa-Carleton Health Department. Please feel free to copy.