19 PURPLE Wildflowers in Idaho! (ID Guide)

Did you find a purple wildflower in Idaho?

Common Idaho Purple Wildflowers

If so, I’m sure you’re wondering what type of wildflower it is! Luckily, you can use this guide to help you identify it. 🙂

 

Today, we will look at 19 common wildflowers that are purple in Idaho.

 

You will notice a USDA Hardiness Zone for each wildflower listed in the article. This refers to areas of the US where plants can grow based on temperature. Here is a map showing the hardiness zones of Idaho:

Hardiness Zones in Idaho range from 1a to 13b.

 

19 types of purple wildflowers in Idaho:

 


#1. Bull Thistle

  • Cirsium vulgare

Types of Purple Wildflowers that live in Idaho

Also known as Boar Thistle, Common Thistle, Dodder, and Spear Thistle.

Growing Information

  • USDA Hardiness Zone: 3a-8b
  • Life Cycle: Biennial
  • Approximate mature size: 2-6′ (.6-1.8 m)
  • Bloom Time: Summer, Fall
  • Sun Exposure: Full Sun, Sun to Partial Shade

 

Bull Thistle is a spiny and common purple wildflower in Idaho.

 

So be careful if handling! It’s also a great flower if you want to attract giant bees and butterflies.

 

The seeds of this thistle are the preferred menu item for the American Goldfinch. However, these birds also use the thistledown to line their nests; thus, they wait until the flowers bloom in late summer to raise their young.

 


#2. Alfalfa

  • Medicago sativa

Kinds of Purple Wildflowers in Idaho

Also known as Lucerne.

Growing Information

  • USDA Hardiness Zone: 3a-11
  • Life Cycle: Perennial
  • Approximate mature size: 1-3′ (30-90 cm)
  • Bloom Time: Spring, Summer, Fall
  • Sun Exposure: Full Sun

 

Farmers often plant alfalfa as a food crop for farm animals, and it fixes nitrogen from the air into the soil through its roots.

 

This purple wildflower is native to warmer climates and attracts many bees, butterflies, and birds.

 


#3. Smooth Blue Aster

  • Symphyotrichum laeve

Idaho Purple Wildflowers species

Also known as Glaucous Aster and Michealmas Daisy.

Growing Information:

  • USDA Hardiness Zone: 3-9
  • Life Cycle: Perennial
  • Approximate mature size: 1-3′ (30-90 cm)
  • Bloom Time: Summer, Fall
  • Sun Exposure: Full Sun, Partial Sun

 

You will find this striking purple wildflower in plains, meadows, and hillsides throughout Idaho.

 

Like the hairs on a dandelion, the Smooth Blue Aster pappi (ring of fine feathery hairs surrounding seeds) allows the seeds to be spread by the wind.

 


#4. Winter Vetch

  • Vicia villosa

Common Purple Wildflowers species in Idaho

Also known as Vicia Species, Fodder Vetch, and Hairy Vetch.

Growing Information:

  • USDA Hardiness Zone: 4-7
  • Life Cycle: Annual, Biennial, Perennial
  • Approximate mature size: 1-3′ (30-91 cm)
  • Bloom Time: Summer, Fall
  • Sun Exposure: Full Sun, Sun to Partial Sun

 

Often gardeners plant Winter Vetch as a companion plant to tomatoes. This is done because the Winter Vetch helps put nitrogen in the soil, which helps keep weeds from sprouting.

 

This purple wildflower grows in various places such as forests, grasslands, meadows, old fields, roadsides, and disturbed areas. It also is considered invasive in some areas.

 


#5. Common Burdock

  • Arctium minus

purple wildflowers

Also known as Lesser Burdock, Little Burdock, Louse-bur, Button-bur, Cuckoo-button, and Wild Rhubarb.

Growing Information:

  • USDA Hardiness Zone: 4a-10b
  • Life Cycle: Biennial
  • Approximate mature size: 4-6′ (120-180 cm)
  • Bloom Time: Mid Summer, Late Summer, Early Fall, Mid Fall
  • Sun Exposure: Sun to Partial Shade

 

You will find this purple wildflower in pastures, open prairies, hayfields, roadsides, old fields, barnyards, railways, and other disturbed areas in Idaho.

 

Common Burdock has large leaves and deep purple flowers resembling rhubarb, making this plant easy to identify. After the flower head dries, they are similar to velcro because they stick onto humans and animals to transport the entire seed head.

 

This purple wildflower attracts bees, butterflies, and birds. Powdery mildew and root rot often affect it. But be careful if you handle this plant; it may cause skin irritation or an allergic reaction.

 


#6. Clasping Venus’ Looking Glass

  • Triodanis perfoliata

purple wildflowers

Also known as Roundleaf Triodanis and Clasping Bellflower.

Growing Information:

  • USDA Hardiness Zone: 2-11
  • Life Cycle: Annual
  • Approximate mature size: 6-36″ (15-91 cm)
  • Bloom Time: Spring, Summer
  • Sun Exposure: Full Sun

 

In Idaho, you can find this purple wildflower in habitats with dry sandy soils such as disturbed areas, gardens, and woods.

 

You can identify the Clasping Venus’ Looking Glass by looking for the flowers blooming in the rounded leaves. This plant can self-pollinate and attracts small butterflies, bees, and flies.

 


#7. Kudzu

  • Pueraria montana

purple wildflowers

Also known as Japenese Arrowroot, Kudzu Bean, and Kudzu Vine.

Growing Information

  • USDA Hardiness Zone: 5b-11
  • Life Cycle: Perennial
  • Approximate mature size: 30-100′ (9.1-30 m)
  • Bloom Time: Summer, Fall
  • Sun Exposure: Full Sun, Sun to Partial Shade

 

This climbing purple wildflower climbs surfaces such as trees, cliffs, and walls and grows as ground cover if there are no vertical surfaces.

 

Kudzu is a widespread purple wildflower and is INCREDIBLY INVASIVE in Idaho. The seeds spread quickly from human actions, along with mammals and birds.

 


#8. Bee Balm

  • Monarda fistulosa

purple wildflowers

Buy/View Seeds HERE!

Also known as Wild Bergamot, Horsemint, and Wild Bee Balm.

Growing Information

  • USDA Hardiness Zone: 3a-9b
  • Life Cycle: Perennial
  • Approximate mature size: 2-4′ (60-120 cm)
  • Bloom Time: Summer
  • Sun Exposure: Sun to Partial Shade

 

Look for this fragrant clump-forming perennial with beautiful lilac-purple wildflowers in dry areas of fields, prairies, and along roads in Idaho.

 

Bee Balm leaves make a refreshing tea that provides many health benefits, as its antimicrobial properties help ward off colds and the flu. Steaming the plant can also help clear nasal passages while creating a poultice from Bee Balm could prove helpful in treating headaches, sores, muscle cramps, or fungal infections. Lastly, Monarda can stimulate uterine contractions, so expecting women shouldn’t use it.

 

The main reason that I grow Bee Balm in my flower garden is to attract hummingbirds, butterflies, and pollinator bees. When this NATIVE perennial is in full bloom, birds and insects won’t be able to resist visiting the nectar-rich flowers. Many people claim that Bee Balm is so effective at drawing in hummingbirds that they no longer have to worry about filling their feeders!

 


#9. Spotted Knapweed

  • Centaurea stoebe

purple wildflowers

Also known as Panicled Knapweed.

Growing Information

  • USDA Hardiness Zone: 3a-10b
  • Life Cycle: Biennial
  • Approximate mature size: 2-3′ (60-90cm)
  • Bloom Time: Summer, Fall
  • Sun Exposure: Full Sun

 

You will usually find these wildflowers along roads and open fields throughout Idaho.

 

This purple wildflower is considered a weed in many places because it can crowd out other plants. However, it is also an allelopathic plant, which chemically changes the soil to discourage other plants from growing and favor its offspring. I can’t believe how rude Spotted Knapweed can be, but it is an effective evolutionary advantage!

 


#10. Creeping Charlie

  • Glechoma hederacea

purple wildflowers

Also known as Gill-over-ground, Ground Ivy, Hedgemaids, Field Balm, Tunhoof, Catsfoot, Run-away-robin, and Alehoof.

Growing Information

  • USDA Hardiness Zone: 3a-10b
  • Life Cycle: Perennials
  • Approximate mature size: 5-8″ (12.5-20 cm)
  • Bloom Time: Spring, Summer
  • Sun Exposure: Sun to Partial Shade

 

This plant grows in large groups in moist semi-shaded areas and tolerates the sun very well. Many species of wild bees collect pollen from the Creeping Charlie as well.

 

This purple wildflower is invasive in some places. For example, it is considered an aggressive weed in woodlands and lawns in Idaho mainly because the plant’s extensive root system makes it difficult to get rid of by hand-pulling or mowing. I have personally battled with Creeping Charlie in my yard before!

 


#11. New England Aster

  • Symphyotrichum novae-angliae

purple wildflowers

View/Buy Seeds HERE!

Also known as Hardy Aster and Michaelmas Daisy.

Growing Information

  • USDA Hardiness Zone: 3a-9b
  • Life Cycle: Perennial
  • Approximate mature size: 3-7′ (90-210cm)
  • Bloom Time: Fall
  • Sun Exposure: Late Summer, Early Fall

 

New England Aster generally grows in wet environments in Idaho, although this purple wildflower can survive in dry soil or sand.

 

This purple wildflower is a great perennial for your garden because of its long bloom time in autumn. In addition, if you allow seed heads to dry on the plant, you can remove and collect the seeds for future plantings.

 


#12. Tall Morning Glory

  • Ipomoea purpurea

purple wildflowers

Also known as Purple Morning Glory and Common Morning Glory.

Growing Information

  • USDA Hardiness Zone: 2-11
  • Life Cycle: Annual
  • Approximate mature size: 12-15′ (3.7-4.6 m)
  • Bloom Time: Summer, Fall
  • Sun Exposure: Full Sun, Sun to Partial Shade

 

This purple wildflower is considered a weed, and it can grow in dry and rich soil. Look for this perennial in gardens, old fields, roadsides, and waste sites.

 

Tall Morning Glory seeds have been used as psychedelic in the past. As a result, the seeds you find for sale are commonly treated with toxic methylmercury, which serves as a preservative and a poison to discourage recreational use.

 


#13. Purple Coneflower

  • Echinacea purpurea

purple wildflowers

View/Buy Seeds HERE!

Also known as Eastern Coneflower and Eastern Purple Coneflower.

Growing Information

  • USDA Hardiness Zone: 2a-10b
  • Life Cycle: Perennial
  • Approximate mature size: 2-3′ (60-90 cm)
  • Bloom Time: Summer, Fall
  • Sun Exposure: Full Sun, Sun to Partial Shade

 

Purple Coneflower is extremely hardy, which is why people love growing them in their gardens in Idaho. These flowers are also heat and drought-resistant, which means they will thrive in harsh conditions.

 

The cone-shaped disc comprises several smaller flowers, which contain loads of nectar. The colorful blooms draw the attention of bees, butterflies, and hummingbirds.

 

Make sure to select an appropriate place in your landscaping beds, as Purple Coneflower grows anywhere from two to four feet high. In addition, coneflowers grow in clumps or clusters up to two feet wide. So be sure to give your plants plenty of room to thrive!

 


#14. Canada Thistle

  • Cirsium arvense

purple wildflowers

Also known as Canadian Thistle, Lettuce From Hell Thistle, California Thistle, Corn Thistle, Cursed Thistle, Field Thistle, Green Thistle, Hard Thistle, Perennial Thistle, Prickly Thistle, Small-Flowered Thistle, Way Thistle, and Stinger-needles.

Growing Information

  • USDA Hardiness Zone: 3a-10b
  • Life Cycle: Perennial
  • Approximate mature size: 1-5′ (30-150 cm)
  • Bloom Time: Late Spring through Early Fall
  • Sun Exposure: Full Sun to Partial Shade

 

This purple wildflower is an incredibly invasive weed in Idaho.

 

This non-native wildflower occurs in various habitats such as wetlands, grasslands, forests, and meadows. It reproduces fast because each plant can have up to 5,300 seeds!

 

Watch out for these wildflowers’ leaves; they are very spiny, and it would not feel good to touch them.

 


#15. Bittersweet Nightshade

  • Solanum dulcamara

purple wildflowers

Also known as Bittersweet, Bitter Nightshade, Blue Bindweed, Amara Dulcis, Climbing Nightshade, Fellenwort, Felonwood, Poisonberry, Poisonflower, Scarlet Berry, Snakeberry, Trailing Bittersweet, Trailing Nightshade, Violet Bloom, and Woody Nightshade.

Growing Information

  • USDA Hardiness Zone: 4a-8b
  • Life Cycle: Perennial
  • Approximate mature size: 2-8′ (60-240 cm)
  • Bloom Time: Spring, Summer, Fall
  • Sun Exposure: Sun and Light Shade

 

Look for this woody vine in woodlands, scrublands, hedges, and marshes. This purple wildflower has adorable little berries that some birds eat.

Please be aware that all the parts of the Bittersweet Nightshade are poisonous to humans if ingested. And its foliage is toxic to animals as well. So this is not a plant you want to add to your salad!

 


#16. Great Blue Lobelia

  • Lobelia siphilitica

purple wildflowers

Also known as Great Lobelia and Blue Cardinal Flower.

Growing Information

  • USDA Hardiness Zone: 4a-9b
  • Life Cycle: Perennial
  • Approximate mature size: 1-4′ (30-120 cm)
  • Bloom Time: Summer, Fall
  • Sun Exposure: Sun to Partial Shade, Light Shade

 

This perennial flower does not self-pollinate and must be pollinated by insects, bumblebees, or hummingbirds.

 

This purple wildflower thrives in moist to wet soils and partially shaded environments, including swamp forests, roadside ditches, floodplains, lake margins, and wet prairies.

 


#17. Field Thistle

  • Cirsium discolor

Field Thistle

Also known as Pasture Thistle.

Growing Information

  • USDA Hardiness Zone: 3-9
  • Life Cycle: Perennial
  • Approximate mature size: 3-5′ (90-150 cm)
  • Bloom Time: Summer
  • Sun Exposure: Full Sun

 

Field Thistle has large flower heads that are full of nectar and pollen. Consequently, this is very attractive to large butterflies like migrating monarchs, bees, wasps, bumblebees, and hummingbirds.

 

This invasive purple wildflower is found in damp areas in full sun along roads and open fields in Idaho. Look for its spines or sharp edges and use extreme caution when handling. This plant can poke you!

 


#18. Purple False Foxglove

  • Agalinis purpurea

purple false foxglove

Also known as Purple Gerardia.

Growing Information

  • USDA Hardiness Zone: 2a-10b
  • Life Cycle: Annual
  • Approximate mature size: 12-36″ (30-91 cm)
  • Bloom Time: Summer, Fall
  • Sun Exposure: Full Sun

 

The Purple False Foxglove is a pretty purple wildflower you can add to your garden in Idaho. It prefers moist sandy soils for it to thrive.

 

This semiparasitic plant derives some of its nutrients from other plants around them, such as native grasses, Loblolly Pines, Sycamore, or Sweetgum Trees.

 


#19. Hookedspur Violet

  • Viola adunca

hookedspur violet pic

Also known as Sand Violet, Early Blue Violet, Hookedspur Violet, and Western Dog Violet.

Growing Information

  • USDA Hardiness Zone: 4b-9a
  • Life Cycle: Perennial
  • Approximate mature size: 4-8″ (10-20 cm)
  • Bloom Time: Mid Spring, Late Spring, Early Summer
  • Sun Exposure: Sun to Partial Shade, Light Shade

 

As their name suggests, this purple wildflower is often found in the mountains at varying elevations in Idaho. But it doesn’t necessarily HAVE to grow in the mountains and is found farther below.

 

This violet has seeds that contain oil that attracts ants, that carry the seeds to their nests. And this is how the Hookedspur Violet primarily spreads its seeds to new areas.

 


Do you need more help identifying purple wildflowers in Idaho?

 

Check out this guide!

 


Which of these purple wildflowers have you seen before in Idaho?

 

Leave a comment below!

 

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