Perennials
Should you cut perennials back in the fall? The answer depends on the plant and your gardening goals.
Trim back herbaceous perennials that are prone to disease( such as peonies, daylilies, and irises) to 7 – 10 cm above the ground. However, leave perennials like coneflowers, black-eyed Susans, ornamental grasses, and sedums standing. Their seed heads provide food for overwintering birds, and their structure adds winter interest to the landscape. I love to look out on my garden in winter and admire the sculptures that nature has created with snow and ice on my still-standing perennials.
Roses should not be heavily pruned in fall. Simply remove dead or damaged canes and tie up the stems to protect them from wind damage. Tender shrub roses can be“ hilled up” with a mound of soil or mulch at their base to protect grafts from severe winter temperatures.
Now is the time to plant spring-blooming bulbs like tulips, daffodils, and crocuses. Aim to plant bulbs by mid-October so they can root before the ground freezes. Add a layer of mulch or dried leaves to bulb beds to moderate soil temperatures and encourage moisture.
Yard Care
Rake leaves so they don’ t smother the grass over winter, and use them as mulch in your garden beds. Run them over with a mulching mower( if you have one) and return them to the lawn or garden to feed the soil. After lawn growth stops, give it a final mowing, to about 5 cm, to prevent matting under the snow and discourage the development of snow mould.
While many gardeners strive for a spotless garden before winter, a too-clean yard deprives beneficial insects of essential winter habitats. Hollow stems, leaf litter, and standing dead plant material provide places for solitary bees, butterflies, and ladybugs to overwinter.
Mind Your Tools
Clean soil off shovels, trowels, and pruners. Sharpen blades and coat metal parts with vegetable oil to prevent rusting. Drain garden hoses and store them indoors to prevent cracking.
If you have a compost bin, turn it one last time before the freeze, and add a mix of green( fresh) and brown( dried) material. Your compost pile will go mostly dormant during winter but will be ready to spring to life again as temperatures rise.
Looking Ahead
Finally, walk through your garden and make notes for next year. What plants thrived? Which ones struggled? Are there bare spots where you could plant pollinator-friendly species next spring?
Your cleanup efforts will pay off next season, and your efforts to leave insect and bird habitats will support Alberta’ s biodiversity through the long, cold winter.
So grab your rake, pruners, and gloves— it’ s time to put your garden to bed for another year.
Gerald Filipski finds that fall is his favourite time of the year. The cooler days allow him to enjoy the end-of-season colours and the harvests the fall brings. It’ s time to enjoy the more relaxed atmosphere that fall brings to the garden.
AUTUMN 2025 | 13