Canada Thistle: From Weed to Flower

Each year in late June, Canada Thistles bloom in Eliza Howell Park.


Six decades ago and more, one of the childhood chores for my brothers and me was to hoe weeds at our small farm. I remember Canada Thistle as the most dreaded weed; it grows in patches rather than as single plants, and as a result, it slowed me down when I wanted to reach the end of the row quickly.

They were the epitome of “weed.” That was then. Now, I enjoy Canada Thistle as a wildflower with blooms that attract a great variety of watchable insects. When I was young, I rarely noticed the flowers, perhaps because, doing our job well, the plants never got to mature to that point!

Note:  I am omitting – or rather postponing till later – observations on the important role these thistles play in the lives of American Goldfinches in Eliza Howell Park. This comes a little later in the season, when the plants begin to go to seed.

I saw my first Banded Hairstreak butterfly of the year this week in the thistle patch.


The thistle patch is one place I can get butterfly pictures with my phone camera; they are so focused on their food source that I am able to get close.

The following (Eastern Comma, Cabbage White, an unudentified Skipper, and Silver-spotted Skipper) were all photographed this week in the patch.





The thistles still have spines (what we probably called thorns when we were young), but they don’t seem to bother me now as I walk among the plants.


Below is a sampling of other pollinating insects present this week.


I have learned a few things about Canada Thistle that I didn’t know when I was attacking them with a hoe. One is that they spread by creeping roots, not just by seed; a single plant can colonize an area up to 6 feet in diameter in 2 years. The roots are both vertically deep and horizontally long. Now I know why they kept coming back even though they never went to seed!

The key difference between “a weed” and “a flower” is, it seems, whether it is wanted or not in a particular location. I still remove the thistle “weeds” from our garden, but in the natural areas of the park, l enjoy the thistle “flowers.”

2 thoughts on “Canada Thistle: From Weed to Flower

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s