Most people mow over thistles, spray them, dig them out, eradicate them. We let several of these tall bull thistles grow each year.
These plants are biennials. In late summer thistle rosettes appear in various places around the yard. We note where they are and pick out a few to avoid with the mower.
Lots of Thistles
There are invasive thistles. Musk thistle is found in this area. Their flowers are a gorgeous color, but the plants are definitely unfriendly. We’ve never had them here.
Tall thistles do grow in the pastures. These native thistles have few spines and are the earliest to bloom.
Bull thistles are the ones that showed up in the yard. They are also native. Unfortunately they do have spines.
There are others, but those are the most common around here.
Why Let Thistles Grow?
If you check the labels on bird seed, many mixtures have thistle seed in them. Birds, especially goldfinches love thistle seed. These golden birds feed their young the seed and line their nests with the downy comas.
The value of tall bull thistles goes beyond this. The flowers attract lots of bees, bumblebees, wasps, butterflies and hummingbirds. Since each flower is actually a cluster of many flowers and each has plenty of nectar, the flowers are very popular.
Amazing Plants
Normally these plants grow about four feet tall with many branches. Not this year. This year our tall bull thistles topped out about eight to ten feet. We had to prop them up against the wind.
These are late bloomers so we watched as the stems got taller and taller. Finally they put out branches with buds on the tips.
Other, smaller plants were already blooming. Goldfinches abandoned the bird feeder to hang on the thistle branches and gorge on thistle seed.
Now the tall bull thistles are in full bloom. The hummingbirds make daily forays. Soon the goldfinches will mob them.
And next year more will grow.
