T
The Daily Insight

What does purple thistle look like

Author

Mia Kelly

Published Mar 08, 2026

The purple starthistle’s lavender to deep-purple flowers grow atop spine-tipped bracts. … Growing up to 8 feet tall, the Italian thistle blooms clusters of one to five pinkish, cylinder-shaped flower heads and has spiny-toothed, lobed leaves that have rigid, distinct spines between the leaf segments.

Is purple thistle poisonous?

It may look dangerous, but it is not poisonous. In fact, it has an edible stem.

Where do purple thistles grow?

It is often found along the edges of salt marshes, fields, shores, savannahs, roadsides, and waste places. It is also a pasture weed in the South. It grows best in sandy soil. It is a high-value nectar plant for bees and butterflies and the birds eat the seeds.

What is purple thistle?

Purple thistle (Cirsium horridulum) is a larval host for the Little metalmark (Calephelis virginiensis) and Painted lady (Vanessa cardui) butterflies. The seeds are an important food source for seed-eating birds. … No wonder this species’ name is horridulum! All parts of the plant, including the seeds, have sharp spines.

How do you get rid of purple thistles?

Apply herbicides to kill thistle, especially in spring and fall, before thistles can flower and seed. Use glyphosate for your garden, and use a broad-leaf herbicide containing 2,4-D or MCPP for your lawn. Since glyphosate kills all plants, you must keep application specific.

Is thistle good for anything?

Native thistle provide important habitat and food sources for native fauna. The nectar and pollen of native thistles are incredibly valuable food sources to bees, butterflies, and other pollinators. Many insects feed on the leaves, stems, flowers and seeds, while some songbirds also feed on thistle seeds.

Why is thistle bad?

They’re ready to spew thousands of seeds to continue their spread. These thistles, musk and plumeless thistles, are invasive, noxious weeds that take over entire fields and render the land useless to native wildlife and plants.

What is the difference between thistle and milk thistle?

While all thistles share similarities, only milk thistle has green and white marbled leaves. Both bull thistle and milk thistle have sharp, spiny bracts surrounding the flower head, but those found on bull thistle are smaller and denser.

How do I identify my Canada thistle?

Canada thistle stands erect to 3-1/3 feet (1 m) tall and grows in clumps or patches. Its stems are slender and hairless or nearly hairless. Leaves are oblong to lance shaped, mostly 2 to 8 inches long (5–20 cm), prickly, and are alternate to one another along the stem.

Are thistle an invasive species?

It grows throughout North America, and is considered an invasive species in pastures and forestland. However, bull thistle mostly grows where soil has been disturbed, either along roadsides, or in overgrazed pastures.

Article first time published on

Is thistle a perennial or an annual?

All thistles addressed in this guide are annual to biennial in growth form. They reproduce solely by seed and are prolific seed producers. The seed remains viable in the soil for many years. At maturity, these spiny weeds have basal rosettes, purplish disk flowers, and flowering stems that are highly branched.

What does the milk thistle plant look like?

Milk thistle is a large and highly distinctive thistle, with white marbling on the shiny green leaves. Flowerheads are bright magenta or purple, with thick, fleshy, spine-tipped bracts protruding around the base off the flowerhead. Leaves, stems and flowers are all armed with stiff, sharp spines.

How do I permanently get rid of thistle?

Apply herbicides to kill thistle, especially in spring and fall, before thistles can flower and seed. Use glyphosate for your garden, and use a broad-leaf herbicide containing 2,4-D or MCPP for your lawn. Since glyphosate kills all plants, you must keep application specific.

How do I get rid of thistle in hay fields?

  1. 1 Scout your pasture in late winter and early spring.
  2. 2 Look for thistle seedlings.
  3. 3 Use controlled burns for severe infestations.
  4. 4 Treat small thistles directly with herbicide.
  5. 5 Treat your entire pasture if you have adult thistles.

How do you remove thistle weeds?

Your best bet is to pull on some heavy, leather gloves and fight the beast by hand. Use a trowel to dig up young thistles early in the season. Thistles have a widely spreading rhizome system, so dig out as much as you can. You can also use pruning shears to cut the thistles back at ground level.

What is the difference between a thorn and a thistle?

Thistles are non-woody plants that are outfitted with prickles, one of the three different kinds of plant armor recognized by botanists. Thorns are modified branches. Spines are modified leaves.

Can you eat purple thistle?

The leaves are still edible if you strip them of spines as are the bottom of the flower buds, though the bud bottoms aren’t much more than a nibble. All can be eaten raw, steamed or boiled. (Or roast whole by a fire and squeeze the cooked core out.)

Can you eat a thistle?

Unlike many wild plants that must be cooked in two waters to detoxify plant parts or minimize harsh tastes, thistle tastes fine raw. Try it—just strip off the spines and have a taste—it’s mild. … Yes, and you don’t have to worry about snipping off the spines with a scissors.

What medications should not be taken with milk thistle?

  • Allergy drugs. …
  • Drugs for high cholesterol. …
  • Anti-anxiety drugs. …
  • Antiplatelet and anticoagulant drugs (blood thinners). …
  • Some cancer drugs. …
  • Drugs broken down by the liver.

What's a thistle look like?

Look for mostly hairless, green and oblong leaves that have edges with spine-tipped lobes to spot the yellow thistle (Cir. horridulum). The yellow thistle has thick, hairy, 2- to 5-foot stems and buff-yellow to reddish-purple flower heads that sit atop a whorl of spiny leaves.

What plants look like thistles?

Basket flower can be mistaken for a thistle when you first see it. The flower has a similar profile and color. But luckily it lacks the prickly characteristics. Basket flower or Centaurea americana is pretty enough to make the cover of the popular field guide Wildflowers of Texas by Geyata Ajilvsgi.

How do I know if I have native thistle?

The basal rosettes and general leaf morphology are the features to use for identifying which are native and which are non-native before they flower. The ones that occur in Hays County or in adjacent counties are: Cirsium horridulum (Yellow thistle), despite its unfortunate species name, is a native of Central Texas.

Can Canada thistle be eaten?

Edibility: Young Canada thistle leaves are edible and remarkably tasty. … Young thistles or thistle tops can also be boiled as a potherb. The stalks, while still flexible, can be peeled and eaten raw. The plants seem highly nutritious and might make a healthy green drink with the aid of a blender.

What's the difference between bull thistle and Canadian thistle?

If the thistle has rhizomes—or roots that extend out from one plant to grow another plant nearby—then it is likely a Canada thistle. If it does not have rhizomes but has a taproot and has spiny wings up the length of its stem that is needle-shaped, then it is a bull thistle.

What part of a thistle is edible?

In addition to the root, the stems are edible, when peeled. However, the thistle contains inulin, which gives some people digestive issues.

Is thistle poisonous to dogs?

Milk thistle appears to be a safe and well-tolerated herb for animals. Side effects are usually mild and often involve the gastrointestinal tract, such as loose stools or mild digestive upsets.

Do thistles grow back?

Thistles are perennial weeds that grow back year after year forming deeper and deeper roots as it establishes itself. They don’t tolerate mowing well though and this on its own can be enough to get rid of them.

Do thistles spread?

Perennial sow-thistle spreads by underground roots but, in contrast to creeping thistle, these are largely confined to the surface 15 cm. Spread by seed is also important and these are dispersed by wind. Seeds may survive up to 5 years in soil and seedling emergence is largely confined to the spring.

What to do with thistles after flowering?

Cut wilting flowers off as they die and cut the plant back very short in fall. During the summer season, it’s important to water in case strong of extended drought.

Does milk thistle have a look alike?

Short-styled thistle (Cirsium brevistylum) looks similar to edible thistle, but with less-lobed leaves and clustered flower heads. Only bottoms of leaves are slightly fuzzy. Mature short-styled thistle, showing less-lobed leaves than edible thistle.

What does milkweed thistle look like?

Milkweed usually grows to about 2 feet tall. It has large, bright clusters of flowers on the tops of its stems. … The main stem of a milk thistle is stout and ridged and can grow to over 6 feet tall. Large, broad leaves protrude from either side of the main stem, with branching shoots jutting out as well.