I had quite an experience yesterday August 24, 2026.
Following Mitchell Fox’s CBC article, Invasive plants are available across Canada. Is federal regulation possible?, I was invited to do a CBC Radio syndication interview. Not one to shy away from a new experience, I said sure.
What did that mean? Well, yesterday I spent four hours, off and on, talking to 17 different CBC hosts from across the country.
It was an enormous privilege but, frankly, quite overwhelming. Each interview was only about five minutes, so there was barely time to catch my breath before the next host was calling from another part of Canada.
In those brief conversations, I responded to some variation of the same five or six questions:
- How does gardening factor into the spread of invasive plants?
- What are invasive plants, and what harm do they actually do?
- What should I be worried about here?
- What would regulation mean for the people who grow and sell these plants?
- What should I plant instead?
Five minutes was never enough for any of them.
I tried to make the case for better regulation of invasive plants that can cause harm to our economy, environment and, in some cases, public health. I was better in some interviews than others at giving concrete examples, because the examples and the risks change from one region to another.
Depending on the region, I talked about plants such as tree-of-heaven, goutweed, periwinkle, yellow flag iris, Tartarian honeysuckle and scilla. In the prairie provinces and northern territories, I mentioned caragana, or Siberian pea shrub, and the work being done to control it in places where it is displacing native vegetation and altering grassland and shrubland habitats. In Nova Scotia, one host was dealing with knotweed in her own backyard, so we talked about the damage these plants can do to riparian systems, the enormous costs of control seen in places such as the United Kingdom, and the importance of getting ahead of emerging problems rather than waiting until they become widespread and expensive.
I tried to explain some of the characteristics that can make a plant invasive: its ability to reproduce and spread, escape natural enemies, outcompete other plants, alter the environment around it, and persist despite attempts to control or remove it.
Did I always find the right example? Probably not. Switching from region to region and trying to identify the most locally relevant concern was challenging.
Did I make the bigger picture clear? Again, probably not in five minutes. But perhaps I planted a few seeds of doubt. Maybe someone will look at a plant in a garden centre and think: Before I buy this, I wonder if it could become a problem here?
And that, in itself, would be a worthwhile outcome.
WHAT THE QUESTIONS REVEALED
Going through this rapid-fire questioning process made the underlying problem increasingly clear.
While some people and organizations know a great deal about invasive plants in Canada, we don’t have a system that effectively brings that knowledge to consumers and sellers. We don’t have a consistent way to reduce the flow of potentially invasive plants into our gardens and landscapes.
Canada has a patchwork of provincial and federal regulations. Some provinces regulate a handful of horticultural plants that pose serious risks. Quebec’s new regulation, in force since June 2026, prohibits the sale and commercial propagation of 31 priority invasive plant species, and Manitoba prohibits 21 invasive aquatic plants under its Water Protection Act. These are models for change. But many jurisdictions have no framework at all, and all are struggling for the resources to screen and address a growing problem.
Governments from the municipal to national level, invasive species councils, conservation organizations, botanical gardens, Master Gardeners and many others are doing important work identifying problems and educating the public.
But we are not effectively bringing that information together across borders.
Again and again, hosts came back to the same question:
“What invasive plants are being sold in my local garden centres, and how do I know which ones are a concern?”
I pointed hosts toward Grow Me Instead guides where they were available and encouraged listeners to support regional native flora and keystone species, the plants that support the most local wildlife.
One thing became very clear during those 17 conversations: We need a national coordinating body to develop a national database of invasion risks. It would be a trusted, science-based resource that brings together the available evidence and identifies potential risks across different regions of Canada. A gardener, retailer or regulator should be able to enter a plant name and find its invasion risk for the regions of Canada where it might be sold or planted.
Plants that pose an unacceptable risk should be phased out of the marketplace. Others could carry clear labels about their potential to spread and cause harm, along with safer alternatives.
Over the coming weeks, I’ll look at what is happening in different provinces and territories. What is regulated? What invasive plants are recognized as problems? What resources are available to gardeners? And try to help identify significant gaps.
There are some wonderful examples of leadership across the country. There are also some surprising inconsistencies.
Let’s start next week in Atlantic Canada.
I welcome folks from various regions to provide posts and input.
