Common Buckeye Host Plant: Essential Guide for Gardeners

The common buckeye butterfly, scientifically known as Junonia coenia, is a distinctive North American species with easily recognizable target-shaped eyespots. Inhabiting open, sunny landscapes such as old fields, roadsides, gardens, and parks, these butterflies can be found throughout the year, depending on the region.

An essential aspect of the common buckeye’s life cycle is its relationship with host plants, particularly during its caterpillar stage. Caterpillars of this species feed on leaves from a variety of plants, with their preferences including members of the figwort family (Scrophulariaceae) like snapdragon, toadflax, and figwort. Other plants that can serve as host plants are monkey flower, plantain, ruellia, verbena, and water speedwell. Knowledge about suitable buckeye host plants can enhance butterfly gardening practices and contribute to the conservation of this charming butterfly species.

Common Buckeye Butterfly: Overview

Junonia Coenia

The Common Buckeye Butterfly, scientifically known as Junonia coenia, is a unique butterfly species found in North America. It thrives in open, sunny landscapes such as fields, gardens, and parks.

Eyespots

These butterflies are easily recognizable due to their distinctive target-shaped eyespots, which serve as a defense mechanism to deter predators.

Wingspan

The Common Buckeye Butterfly has a wingspan ranging from 1 5/8 to 2 3/4 inches, making it a medium-sized butterfly.

Nymphalidae Family

Belonging to the Nymphalidae family, the Common Buckeye shares characteristics with other brush-footed butterflies, like colorful patterns and a variety of host plants.

Resident in Southern United States

Common Buckeyes are primarily residents of the Southern United States, but their range expands during the warmer months. They can be found in Alabama and North Carolina, among other states.

Key Features:

  • Target-shaped eyespots
  • Medium-sized wingspan
  • Part of the Nymphalidae family
  • Found in open, sunny landscapes

Comparison Table:

Feature Common Buckeye Butterfly Other Nymphalidae Butterflies
Eyespots Yes Varies
Wingspan 1 5/8 – 2 3/4 inches Varies
Habitat Open, sunny landscapes Varies
Predominant U.S. Location Southern United States Varies

Host Plants and their Role

Caterpillar Nourishment

The common buckeye caterpillar depends on specific host plants for nourishment. Some examples of host plants include:

  • Plantain
  • Snapdragon
  • False foxglove

These plants provide essential nutrients for the caterpillar’s growth and development.

Adult Butterfly Attraction

Adult buckeye butterflies are attracted to host plants to feed on nectar. Some plants that attract adult buckeyes are:

  • Lantana
  • Butterfly bush
  • Coneflowers

These plants offer nectar-rich flowers, providing energy for adult butterflies.

Egg Laying Sites

Female buckeye butterflies lay their eggs on host plants’ leaf buds and upper leaves1. These sites ensure that the hatched caterpillars have immediate access to a food source. Two comparisons of host plants are shown below:

Host Plant Caterpillar Nourishment Adult Attraction Egg Laying
Plantain Yes No Yes
Butterfly bush No Yes No

In summary, host plants play a vital role in the life cycle of the common buckeye butterfly by providing nourishment for the caterpillars, attracting adult butterflies with nectar, and acting as egg-laying sites for females.

Common Host Plants

Plantain

Plantain (Plantago) is a common host plant for the Common Buckeye butterfly’s caterpillars. Some typical characteristics of plantains include:

  • Wide, flat leaves
  • Small flowers on a tall stalk

Examples of plantain species include lance-leaved plantain (Plantago lanceolata) and broadleaf plantain (Plantago major).

False Foxglove

False foxglove (Agalinis) is another suitable host plant, featuring:

  • Bright, tubular flowers
  • Thin, needle-like leaves

Common species consist of slender-leaved false foxglove (Agalinis tenuifolia) and gerardia (Agalinis purpurea).

Snapdragon

Snapdragon (Antirrhinum) is a preferred host plant with its:

  • Unique, two-lipped flowers
  • Attractive range of colors

Snapdragons offer a diverse range of species such as common snapdragon (Antirrhinum majus) and dwarf snapdragon (Antirrhinum nanum).

Gerardia

Gerardia (Gerardia) is recognized as a host plant option with notable attributes:

  • Pink or purple tubular flowers
  • Opposite, simple leaves

Gerardia flower species include downy gerardia (Gerardia paupercula) and fernald’s gerardia (Gerardia fernaldii).

Ruellia

Ruellia (Ruellia) cater to the Common Buckeye’s needs, showcasing:

  • Tubular flowers in bright colors
  • Opposite, narrow leaves

Wild petunia (Ruellia humilis) and ruellia strepens (Ruellia strepens) are examples of ruellia species.

Toadflax

Toadflax (Linaria) is another host plant, characterized by its:

  • Snapdragon-like flowers
  • Alternate, linear leaves

Common toadflax (Linaria vulgaris) and spurred toadflax (Linaria spartea) are a couple of toadflax species examples.

Comparison Table

Host Plant Flower Type Leaf Characteristics
Plantain Small, on a tall stalk Wide, flat
False Foxglove Bright, tubular Thin, needle-like
Snapdragon Unique, two-lipped Varies by species
Gerardia Pink or purple, tubular Opposite, simple
Ruellia Bright, tubular Opposite, narrow
Toadflax Snapdragon-like Alternate, linear

Life Cycle of the Common Buckeye Butterfly

Eggs and Larva

The life cycle of the Common Buckeye butterfly begins with the eggs. Female butterflies lay their eggs on host plants, such as the snapdragon or plantain. These eggs:

  • Are small, round, and pale green.
  • Hatch into larvae after 3-6 days.

Caterpillar and Spines

Upon hatching, the larvae are called caterpillars. These caterpillars:

  • Have short, unique spines.
  • Feed on host plants to grow quickly.
  • Goes through five growth stages called instars.

Chrysalis and Pupa

After fifth instar, caterpillars:

  • Form a chrysalis for pupation.
  • Pupa stage lasts 10-14 days.

During this stage, the caterpillar undergoes a transformation into an adult butterfly within its protective shell.

Adult Butterfly

The adult Common Buckeye butterfly is known for its distinct eyespots and beautiful patterns. Some features are:

  • Brown color with orange bars and eyespots.
  • Wingspan of 1½ – 2¾ inches (4.2 – 7 cm).
  • Males and females mate to continue the cycle.

Here is a comparison table of the life stages of the Common Buckeye butterfly:

Stage Duration Main Features
Eggs 3-6 days Small, round, pale green eggs laid on host plants
Caterpillar 2-3 weeks Spined larvae feed on host plants, go through five instar stages
Chrysalis 10-14 days Pupa stage where the transformation into adult butterfly occurs
Adult 1-2 months Distinct eyespots, brown with orange bars, wingspan of 4.2 – 7 cm

Predators and Defense Strategies

Camouflage

Common buckeye butterflies employ camouflage as a defense strategy to help them blend in with their surroundings. This reduces their chances of being spotted by predators like birds and insects, who may feed on them.

  • Example: The brown color of the common buckeye’s wings helps them to blend into the plants and soil, making it harder for predators to detect them.

Warning Coloration

Another defense strategy used by the common buckeye is warning coloration. The bright colors like orange and off-white on their wings serve as a signal to predators that they might be unpalatable or even toxic.

  • Example: The orange bars on the leading edge of the forewing serve as an indicator to potential predators that the butterfly may not be a suitable meal.

Eyespots as a Deterrent

The most distinguishing feature of the common buckeye is the eyespots on their wings which serve as a deterrent to predators. These eyespots can make the butterfly appear larger, more intimidating, or even resemble the face of a larger animal, effectively scaring off potential predators.

  • Example: The large eyespots on the common buckeye’s wings can make it seem like a more formidable prey, causing predators to hesitate or avoid attacking.

Comparison Table

Defense Strategy Purpose Examples
Camouflage Blending in The brown color of the wings helps the butterfly blend into its surroundings.
Warning Coloration Signaling unpalatability The orange and off-white colors on the wings serve as a warning to predators.
Eyespots Deterrent The eyespots on the wings can intimidate predators or make the butterfly seem larger.

Landscaping and Gardens

Nectar Plants and Fruit

Creating a butterfly-friendly habitat begins with selecting the right nectar plants and fruit. Some popular options are:

  • Zinnias: These bright flowers attract butterflies with their nectar.
  • Sunflowers: Butterflies love the large, flat, and colorful surfaces for feeding.

Incorporating fruit trees into your landscaping can provide an additional food source for butterflies. For example, butterflies are drawn to the overripe fruit from apple or cherry trees.

Butterfly Bush and Lantana

Two popular butterfly-friendly plants are the butterfly bush and lantana:

  • Butterfly Bush: These shrubs produce long clusters of fragrant flowers and attract various butterfly species.
  • Lantana: This low-maintenance perennial produces bright, clustered blooms that butterflies love.

Here’s a comparison table to help you decide between these plants:

Plant Growth Rate Maintenance Bloom Time Attracts
Butterfly Bush Fast Low Summer-Fall Various Butterflies
Lantana Moderate Low Spring-Fall Butterflies, Bees

Creating Butterfly-Friendly Habitats

In addition to selecting the right plants, consider the following tips for creating a butterfly-friendly habitat:

  • Provide access to water by placing a shallow dish or birdbath in your garden.
  • Offer shelter by including shrubs, trees, or rock piles for butterflies to rest.
  • Minimize pesticide use to protect the butterflies and their host plants.

Geographic Distribution and Habitat

Fields and Clearings

The common buckeye butterfly, Junonia coenia, thrives in open, sunny landscapes. Examples of habitats include:

  • Old fields
  • Roadsides
  • Utility corridors
  • Gardens
  • Parks
  • Yards
  • Fallow agricultural land
  • Scrubs
  • Pine forests

These habitats provide an ample supply of host plants for the common buckeye caterpillars to feed on.

Florida to Mexico

Common buckeyes are well-established in North America, particularly in areas such as Florida and Mexico. Their range extends from the southeastern United States all the way to the southern parts of Mexico. They are known to be highly adaptable, allowing them to inhabit a wide variety of environments.

Tropical Buckeye

The tropical buckeye, Junonia evarete, is a close relative of the common buckeye and can be found in regions with tropical climates. Key differences between the two include:

  • Habitat: Tropical buckeyes favor warmer climates
  • Coloration: Tropical buckeyes have lighter wing coloration
Feature Common Buckeye Tropical Buckeye
Habitat Wide variety Tropical regions
Wing coloration Darker Lighter

Both species have similar habits and host plants, but the tropical buckeye is more restricted to tropical environments, making it less widespread than the common buckeye.

Conservation and Importance

Butterflies and Moths of North America

The Common Buckeye is a species of butterfly that is native to North America. Its host plants play a crucial role in the life cycle of these butterflies, as they provide food for their caterpillars. Some common host plants include:

  • Plantain
  • Snapdragon
  • Verbena

In addition to the Common Buckeye, the host plants support several other species of butterflies and moths across the continent.

Insecticide Use and Impact

Insecticides can negatively affect butterflies, moths, and their host plants. They can:

  • Kill caterpillars and other beneficial insects
  • Reduce the availability of host plants

In some cases, insecticides can even harm the very species they are meant to protect. It is essential to practice responsible insecticide use and consider alternative methods to maintain the balance in our ecosystems.

Insecticide Use Impact on Butterflies, Moths, and Host Plants
Pros Remove pests that may be harmful to host plants
Control invasive plant species
Cons Can kill beneficial insects
Reduce the availability of host plants

By understanding the importance of conservation and being mindful of how our actions can affect the butterflies and moths of North America, we can work together to protect essential host plants while providing a home for these beautiful creatures.

Footnotes

  1. University of Kentucky, Department of Horticulture

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Common Buckeye Caterpillar

 

Common Buckeye Caterpillar
Location:  Newport News, VA
August 2, 2010 5:45 pm
An accompaniment to the Common Buckeye butterfly posted earlier today, here’s its caterpillar, happily chewing up all the snapdragons in the yard! We actually had quite a congregation of Buckeyes a couple days ago and decided they had most likely gathered here in southeast VA in memory of Jack Tatum.
Kathy H

Common Buckeye Caterpillar

Hi Kathy,
We are happy to post your excellent image of a Common Buckeye Caterpillar.

Letter 2 – Common Buckeye Caterpillar

 

Subject:  Unknown Caterpillar Eating Petunias
Geographic location of the bug:  Kansas
Date: 07/18/2019
Time: 08:39 AM EDT
Your letter to the bugman:  I’ve seen this caterpillar eating the petunias. I googled but was unsuccessful identifying the species. Your help is appreciated.
Sincerely,
How you want your letter signed:  Anna

Common Buckeye Caterpillar

Dear Anna,
We tried to identify your caterpillar this weekend, but we were having trouble accessing BugGuide.  We know this is a Brush-Footed Butterfly Caterpillar in the family Nymphalidae, but we needed to determine the species.  We located this identical caterpillar on BugGuide, but alas, it is only identified to the family level.  This BugGuide image leads us to believe you encountered a Common Buckeye Caterpillar.  BugGuide lists host plants as “Plants from the snapdragon family including snapdragon (
Antirrhinum), toadflax (Linaria), and Gerardia; the plantain family including plantains (Plantago); and the acanthus family including ruellia (Ruellia nodiflora).”  Butterfly Fun Facts lists Mexican Petunia (Ruellia species) as a host plant.

Common Buckeye Caterpillar
Daniel,
From your resources and referring back to the caterpillar I concur it looks like a Common Buckeye Caterpillar.
I greatly appreciate your assistance.  Wishing you a wonderful day!
Anna

Letter 3 – Common Buckeye Caterpillar

 

Subject:  What type of catarpillar is this?
Geographic location of the bug:  Midwest Missouri
Date: 08/01/2019
Time: 01:51 PM EDT
Your letter to the bugman:  Hello there!
My 6 year old son found this catarpillar outside and we want to know what kind it is. Is it venomous? What type of tree leaves does it eat? And what kind of butterfly will it become? Thanks so much!
How you want your letter signed:  Sincerely, Momma of Boys

Common Buckeye Caterpillar

Dear Momma of Boys,
This is a Common Buckeye Caterpillar,
Junonia coenia, and it is perfectly harmless.  The Common Buckeye is a beautiful spotted butterfly.  BugGuide lists host plants as “Plants from the snapdragon family including snapdragon (Antirrhinum), toadflax (Linaria), and Gerardia; the plantain family including plantains (Plantago); and the acanthus family including ruellia (Ruellia nodiflora).”  Butterfly Fun Facts lists Mexican Petunia (Ruellia species) as a host plant.

Letter 4 – Drawing of Common Buckeye

 

what kind
March 30, 2010
i found a butterfly that looked odd to me,i mean the colors were odd,i just want to know what kind of butterfly this is it was purple with orange polka dots there was 4 i wasnt able to take a snap shot so i drew one its not the best.
always love ..,marisa l (surname withheld to preserve the anonymity of a child)
on my daisy flowers in my back yard

Common Buckeye, or close relative

Greetings marisa,
We believe you saw a Common Buckeye, Junonia coenia, or a close relative in the same genus.  Common Buckeyes frequent daisies from coast to coast, and there are relatives around the world in the same genus that look similar.  You can compare your drawing to Common Buckeyes we have posted in the past.
We hope you will be starting middle school soon and you will have the opportunity to pursue your natural artistic talent.  Sadly, many school districts are making their budget cuts in the visual and performing arts, and we lament that future young adults will have such a dearth of creativity during their formative years.  Out of the ethical desire to preserve the anonymity of a child, we have withheld your surname.

Letter 5 – Mating Buckeyes: Who's On Top???

 

Buckeye Love
Location:  Central Maryland
August 18, 2010 11:23 pm
These buckeyes are everywhere on my aunt’s Maryland farm. I caught a pair mating. Any idea which gets to perch on the leaf and which is stuck dangling upside down?
Sara

Mating Buckeyes

Hi Sara,
Your photo is so crisp and beautiful and it took absolutely no post-production level or curve control.  Your characteristic curve is perfectly fine.  The details are rendered nicely in the highlights, midtones and shadows.  We do not know the answer to your question, so we played the photography professor’s card.  We think our readership may have fun researching this one for us.

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Common Buckeye Caterpillar

 

Common Buckeye Caterpillar
Location:  Newport News, VA
August 2, 2010 5:45 pm
An accompaniment to the Common Buckeye butterfly posted earlier today, here’s its caterpillar, happily chewing up all the snapdragons in the yard! We actually had quite a congregation of Buckeyes a couple days ago and decided they had most likely gathered here in southeast VA in memory of Jack Tatum.
Kathy H

Common Buckeye Caterpillar

Hi Kathy,
We are happy to post your excellent image of a Common Buckeye Caterpillar.

Letter 2 – Common Buckeye Caterpillar

 

Subject:  Unknown Caterpillar Eating Petunias
Geographic location of the bug:  Kansas
Date: 07/18/2019
Time: 08:39 AM EDT
Your letter to the bugman:  I’ve seen this caterpillar eating the petunias. I googled but was unsuccessful identifying the species. Your help is appreciated.
Sincerely,
How you want your letter signed:  Anna

Common Buckeye Caterpillar

Dear Anna,
We tried to identify your caterpillar this weekend, but we were having trouble accessing BugGuide.  We know this is a Brush-Footed Butterfly Caterpillar in the family Nymphalidae, but we needed to determine the species.  We located this identical caterpillar on BugGuide, but alas, it is only identified to the family level.  This BugGuide image leads us to believe you encountered a Common Buckeye Caterpillar.  BugGuide lists host plants as “Plants from the snapdragon family including snapdragon (
Antirrhinum), toadflax (Linaria), and Gerardia; the plantain family including plantains (Plantago); and the acanthus family including ruellia (Ruellia nodiflora).”  Butterfly Fun Facts lists Mexican Petunia (Ruellia species) as a host plant.

Common Buckeye Caterpillar
Daniel,
From your resources and referring back to the caterpillar I concur it looks like a Common Buckeye Caterpillar.
I greatly appreciate your assistance.  Wishing you a wonderful day!
Anna

Letter 3 – Common Buckeye Caterpillar

 

Subject:  What type of catarpillar is this?
Geographic location of the bug:  Midwest Missouri
Date: 08/01/2019
Time: 01:51 PM EDT
Your letter to the bugman:  Hello there!
My 6 year old son found this catarpillar outside and we want to know what kind it is. Is it venomous? What type of tree leaves does it eat? And what kind of butterfly will it become? Thanks so much!
How you want your letter signed:  Sincerely, Momma of Boys

Common Buckeye Caterpillar

Dear Momma of Boys,
This is a Common Buckeye Caterpillar,
Junonia coenia, and it is perfectly harmless.  The Common Buckeye is a beautiful spotted butterfly.  BugGuide lists host plants as “Plants from the snapdragon family including snapdragon (Antirrhinum), toadflax (Linaria), and Gerardia; the plantain family including plantains (Plantago); and the acanthus family including ruellia (Ruellia nodiflora).”  Butterfly Fun Facts lists Mexican Petunia (Ruellia species) as a host plant.

Letter 4 – Drawing of Common Buckeye

 

what kind
March 30, 2010
i found a butterfly that looked odd to me,i mean the colors were odd,i just want to know what kind of butterfly this is it was purple with orange polka dots there was 4 i wasnt able to take a snap shot so i drew one its not the best.
always love ..,marisa l (surname withheld to preserve the anonymity of a child)
on my daisy flowers in my back yard

Common Buckeye, or close relative

Greetings marisa,
We believe you saw a Common Buckeye, Junonia coenia, or a close relative in the same genus.  Common Buckeyes frequent daisies from coast to coast, and there are relatives around the world in the same genus that look similar.  You can compare your drawing to Common Buckeyes we have posted in the past.
We hope you will be starting middle school soon and you will have the opportunity to pursue your natural artistic talent.  Sadly, many school districts are making their budget cuts in the visual and performing arts, and we lament that future young adults will have such a dearth of creativity during their formative years.  Out of the ethical desire to preserve the anonymity of a child, we have withheld your surname.

Letter 5 – Mating Buckeyes: Who's On Top???

 

Buckeye Love
Location:  Central Maryland
August 18, 2010 11:23 pm
These buckeyes are everywhere on my aunt’s Maryland farm. I caught a pair mating. Any idea which gets to perch on the leaf and which is stuck dangling upside down?
Sara

Mating Buckeyes

Hi Sara,
Your photo is so crisp and beautiful and it took absolutely no post-production level or curve control.  Your characteristic curve is perfectly fine.  The details are rendered nicely in the highlights, midtones and shadows.  We do not know the answer to your question, so we played the photography professor’s card.  We think our readership may have fun researching this one for us.

Authors

    by
  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

    View all posts
  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

    View all posts

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