Hardiness: USDA Zone 3a: to -39.9 °C (-40 °F) USDA Zone 3b: to -37.2 °C (-35 °F) USDA Zone 4a: to -34.4 °C (-30 °F) USDA Zone 4b: to -31.6 °C (-25 °F) USDA Zone 5a: to -28.8 °C (-20 °F) USDA Zone 5b: to -26.1 °C (-15 °F) USDA Zone 6a: to -23.3 °C (-10 °F) USDA Zone 6b: to -20.5 °C (-5 °F) USDA Zone 7a: to -17.7 °C (0 °F) USDA Zone 7b: to -14.9 °C (5 °F) USDA Zone 8a: to -12.2 °C (10 °F) USDA Zone 8b: to -9.4 °C (15 °F)
Sun Exposure: Full Sun Sun to Partial Shade
Danger: Plant has spines or sharp edges; use extreme caution when handling
Bloom Color: Violet/Lavender
Bloom Time: Mid Summer Late Summer/Early Fall
Foliage: Evergreen Silver/Gray
Other details: May be a noxious weed or invasive This plant is attractive to bees, butterflies and/or birds Drought-tolerant; suitable for xeriscaping Average Water Needs; Water regularly; do not overwater Self-sows freely; deadhead if you do not want volunteer seedlings next season This plant is resistant to deer
Soil pH requirements: 6.1 to 6.5 (mildly acidic) 6.6 to 7.5 (neutral) 7.6 to 7.8 (mildly alkaline)
Patent Information: Non-patented
Propagation Methods: From seed; direct sow outdoors in fall
Seed Collecting: N/A: plant does not set seed, flowers are sterile, or plants will not come true from seed
Having researched this plant in a lot of sites, it seems to be closely related to the Scottish thistle, which is a part of many heraldic coats of arms. In addition, the plant is quite handsome, though I will agree that pulling it will require a suit of armor. Still, letting it grow...the stalk has not reached the 3-4 foot level mentioned elsewhere...maybe it is because it is maturing so early.
On Sep 5, 2010, DMersh from Crieff United Kingdom (Zone 7b) wrote:
Native to Britain and Europe, naturalized in USA and elsewhere by accidental spreading of seeds. Can reach almost 6 feet but more commonly between 3-5 feet, may be smaller in very hot or dry locations.
I decided to let one grow to see how big it would get .
It got to be about 4 feet tall and had pretty purple flowers that humming birds and butterflys visited regularly.
I cut the flowers off before the seed fluff could fly.
The kids thought is was pretty cool like having a cactus in Michigan. We are letting one grow this year too, we want to see if we can get a 6 footer.
On Mar 14, 2008, Malus2006 from Coon Rapids, MN (Zone 4a) wrote:
I hate this species - they can be a major pest in lawns - they live forever because they never develop their flower stalks and die - their spines is a danger to barefeet or to pets. Every part of the plant is very sharp - the only good way to get rid of it if it is flowerstalking is to hack it to size and then use a shovel to remove the rootstock. I have only seen them reach flowering size - very tall at about 4 feet tall on roadsides but is rarer in gardens - their single year crowns are more often encounted in lawns and 100% sunny garden locations. In the north, only Canda Thistle is more weedy than this species.
On Apr 1, 2007, Joan from Belfield, ND (Zone 4a) wrote:
This plant is listed on the North Dakota invasive/troublesome list and this information is being distributed in a guide developed by the ND Weed Control Association and other agencies.
Biennial, 3 to 5 feet tall
Purple flowers, 2 inches in diameter
Blooms from July through September
Gumdrop-shaped flower heads up to 3 inches long, spines on flower heads yellow-tipped
Spines on ends of leaves and leaf lobes
Multiple branched stems with purple veins
Leaf surface has a distinct green center vein
Short fleshy taproot
First year plants short, flat rosettes
Widespread invasive usually solitary or in small patches in pastures
Petals can be chewed as gum
Spreads by seed only
On Apr 6, 2006, Vasyr from Valrico, FL (Zone 9a) wrote:
Sure, this plant is quite thorny and pops up everywhere (very quickly, I might add.) However, to add another positive note, it's a drought-tolerant plant which makes it a great plant to use in very hot (and sometimes dry) places like Florida.
Furthermore, Painted Lady, American Painted Lady, and Little Metalmark butterflies all are said to use this plant as a host plant. A great addition to any butterfly garden...
On Jul 10, 2004, EAJStaudt from Bomoseen, VT wrote:
I consider the Bull Thistle one of the most beautiful plants growing wild in my area although most other folks, particularly the farmers, consider them a total hazard. I have had no success in relocating one to my yard, but this year I may have a success.
I hate this 'plant'. To me it's a weed. I spent all last summer digging them out of my garden. Now it has invaded my backyard. Who would call this horrendous pest a plant or would even want it in their garden?
On Jan 25, 2003, lupinelover from Grove City, OH (Zone 6a) wrote:
This plant has been declared a noxious weed in almost every nation in the world.
If you try to hand-pull, make sure the whole taproot is removed; every bit of root left in the soil will re-sprout and grow a new crown. Make sure you wear sufficient protective clothes against this armed enemy: the thorns will penetrate even leather gloves. Multiple applications of chemical herbicides are usually required to kill this.
This plant has been said to grow in the following regions:
Fayetteville, Arkansas Calabasas, California Aurora, Colorado Lamar, Colorado Springfield, Colorado Andover, Kansas Valley Lee, Maryland Eastpointe, Michigan Pinconning, Michigan Smiths Creek, Michigan Minneapolis, Minnesota Cole Camp, Missouri Ojo Amarillo, New Mexico Belfield, North Dakota Glouster, Ohio Kellyville, Oklahoma Dubois, Pennsylvania Crossville, Tennessee Orange, Texas Waxahachie, Texas Millwood, Washington