Thistle plants are a wildflower. Thistle is an invasive weed. Depending upon who you talk to, they are either interested in growing thistle flowers to feed the backyard birds, or trying to get them out of the lawn or backfield. There are hundreds of varieties, many of which, are invasive. They quickly spread through pastures. Cows will not graze near them. Others are grown by gardeners for their flowers. Many of these gardeners, also grow thistle to attract finches to their yards. Goldfinches just love the seeds.
Here are some comments we’ve heard about this plant:
Boy, if you were a thistle plant, you’d probably have a personality complex, suffering from multiple personalities. There is indeed a love-hate relationship….. either you love it, or you hate this plant.
Milk Thistle has medicinal applications and has been in use since the Roman Empire. Most notably, it has been used to treat liver ailments. It has also been used to treat kidney and spleen problems.
What Birds like Thistle Seeds? All kinds of finches, most notably, goldfinches, like the seeds. Mourning Doves, and Juncos, a type of Sparrow, also like thistle. The seeds have lots of fats, nutrients, and protein. They are great for your winter bird feeder.
Did You Know? Artichokes are a member of the Thistle family.
Flowers Bloom: Summer
Flower Colors: Most flowers are Purple. However, there are varieties that produce varying shades of blue, pink, purple, and yellow.
Plant height: 2 to 3 feet tall.
Plant Hardiness Zones: 5 – 9
The plants are grown from seed. They also readily propagate through their roots (rhizomes). New plants develop from buds on the root system. And, in many varieties, this growth is very aggressive.
Final Plant Spacing: Space plants 1 to 2 feet apart.
Days to Germination: Seeds sprout in 14 – 28 days.
Thistle is very easy to grow. They prefer full sun and will thrive in average or better soils. Once they sprouted, there is very little care you need to provide. They will do well all on their own.
If you are growing these plants, use garden glowers. The plants have many sharp thorns.
Ideal pH Level: 6.0 – 6.5.
Plant Problems – Identify the causes and find the cures.
Most herbicides will kill off the plant, but new ones can still emerge from the root system.
So, for established plants, it is important to dig up the rhizomes. And, if you do not remove the entire rhizome, this noxious and invasive weed will regrow.