I have a large Maple on my front yard. I am not sure if it is a Norway Maple or not. It is at the corner of the yard about 32 inches from the yards edge next to the sidewalk and about 25 inches from my neighbour’s front yard. It also slightly slopes towards the sidewalk. Does it make sense to create a circular mulched bed around the tree despite its location?
Thank you for contacting Toronto Master Gardeners with your question. In searching our own database for information for you, there are a number of past responses that address the difficulties of planting under Maples (Acer spp.). You are not alone with your question! Much of the information below comes from these previous answers.
Your photo indicates that you have already been experiencing some difficulties in growing grass underneath your Maple tree. This is due to a number of reasons. The thick canopy and the tree’s own needs for water and nutrients create a shady, dry, nutrient-poor environment. On top of this, the numerous roots make it difficult for plants to get established, and then to thrive.
There are different possibilities for you to consider for under your tree:
- If you decide on the mulched bed, the streetside of the bed will need to be built up to create a levelled area, otherwise there will be runoff of both water and soil with each rainstorm. Additionally, the depth of the soil and mulch you add will need to be only deep enough to avoid digging into, and damaging, the roots of the tree. Lastly, avoid building up the mulch around the base of the trunk to prevent moist conditions that encourage decay of the trunk, insects and diseases.
- For plants in this bed, please have a look at two resources which Toronto Master Gardeners has created: Drought Tolerant Perennials: A Toronto Master Gardeners Guide and Annuals for Shade: A Toronto Master Gardeners Guide. Whether you decide on perennials or annuals, choose ones that do best in dry, shady environments.
- An alternative to a bed would be to place several planters around the tree with annuals or perennials that thrive in shady areas. This avoids the need to create the bed but still provides some colour and interest for you.
- Around my neighbourhood, some gardeners choose to tackle the area immediately around Maple trees in other creative ways such as using decorative stones of varying sizes in patterns and designs, alongside beds or planters.
- On an environmental note, please avoid using invasive groundcovers like Vinca minor (Periwinkle) or Pachysandra terminalis (Japanese Spurge). They continue to be sold in nurseries and are hardy plants for difficult growing conditions but can easily spread to wild areas within the city and outcompete our local native plants. The resource Grow Me Instead, produced by the Ontario Invasive Plant Council, provides some healthy alternatives to frequently-used invasive choices.
Maple trees provide lovely cool shade and beautiful colour in the fall, but they are definitely aggravating to gardeners for many other reasons. Best of luck with whatever direction you choose for around your Maple tree, and your front yard.