I live in Toronto on a ravin lot. I have a very big old maple tree that absorbs all the water and nutrition. Apart from Hostas not much is happy growing in this location. It has few hours of mid day sun
I am looking for recommendation of shrubs and strong showy plants.
Thank you for contacting Toronto Master Gardeners with your enquiry about plant selection for beneath your old Sugar Maple tree.
A good start would be to add organic matter such as well-rotted manure or compost as topdressing for the area to be planted. This improves moisture retention and adds nutrients without disturbing the soil structure.
Additional information on improving soil can be found in this guide:Improving Your Soil Organically: A Toronto Master Gardeners Guide http://www.torontomastergardeners.ca/gardeningguides/improving-your-soil-organically-a-toronto-master-gardeners-guide-2/
This site offers many excellent suggestions for both sun and shade. http://www.torontomastergardeners.ca/askagardener/native-plant-suggestions/
The soil is an important factor in the success of any planting, and since it is beneath a thirsty maple, copious amounts of organic material in the form of compost or other humus would benefit the aeration and moisture holding ability of the planting bed. A raised berm might be an option which also offers the opportunity to enrich the soil.
As to plant selection, since the area is shady and dry, you would choose plants suited to dry shade. Perennials and shrubs with the addition of summer annuals will provide long season colour and form.
In order to have colour from early Spring through to the end of the growing season, you might consider species tulips, and/or other miniature bulbs such as winter aconites (Eranthus hyemalis) or scilla (Scilla siberica) which happily naturalize. Epimedium grandiflorum such as Epimedium x rubrum endure dry sites and offer early blossom, attractive foliage and colourful foliage in autumn.
Shrubs suitable for the site include variegated boxwood Buxus sempervirens variegata pendula which retains its leaves and adds colour all year as do variegated euonymus such as Euonymus fortunei ‘ Canadale Gold’ or E.f. ‘Emerald Gaiety’.
Yucca filamentosa ‘Gold Sword’ has good height, variegated foliage and a tall stunning blossom spike.
Perennials such as Sedum ‘Autumn Joy’ hold their flower heads all winter and the golden groundcover Sedum rupestre ‘Angelina’ retains colour all winter as does its cousin S.r.‘Blue Spruce’
Cheerful Gallardia blooms early summer to fall and Balloon flower Platycodon grandiflorus is slow to emerge but blooms generously at mid-height until late autumn. Bergenia cordifolia with pink blooms in spring makes a statement with its handsome large and shiny evergreen foliage.
We wish you well with your new planting, whether with native plants, or horticultural varieties. Annuals can add a summer splash of colour while the perennials are taking hold.