What We Plant Matters: Reimagining Our Yards as a Butterfly Haven

Throughout the millennia, the astounding beauty of the butterfly has inspired the imagination, the arts, literature, and poetry. Attracting these magnificent creatures into our own yards requires just three basic ingredients:larval host plants, nectar plants, and sheltering habitat.

No Larval Host Plants = No Butterflies
The first ingredient, larval host plants, are the plants caterpillars must eat to survive.  You may be surprised to learn that both shrubs and trees play an important role as hosts in the butterfly garden. According to The Xerces Society, in its excellent book, Gardening for Butterflies, ten times more butterfly and moth species in their caterpillar stage feed upon native shrubs and trees than feed upon wildflowers or grasses.

Caterpillars Eat. Butterflies Sip.
While caterpillars are voracious eaters, butterflies (with a few exceptions) cannot eat, and only sip. This means a butterfly garden must offer both host plants for caterpillars to eat and plants for butterflies to sip nectar. While some host plants (such as milkweed) serve both purposes, your garden should have a wide range of floral resources that bloom successively from early spring until the end of the season.

The second ingredient, nectar plants, should encompass a wide range of flowers (preferably native) with various bloom times and colors. Avoid cultivated flowers that have been manipulated from the open form of the native species into a very dense or “double ruffle” form. Most butterflies and other insects won’t be able to access the floral resources of these complicated (or even sterile) plants.

A monarch butterfly getting ready to emerge (eclose). Witnessing this metamorphosis is always a thrill.
(Photo credit: Vicki Bonk)

Butterflies Are Insects So Avoid Using Insecticides
Any plants you include in your butterfly garden should be free of insecticides. Plants purchased from garden centers may have been treated with systemic insecticides. According to The Xerces Society, “Unlike older classes of insecticides that were formulated to kill pests on contact, systemic insecticides are absorbed by plants upon application and then distributed throughout plant tissues, sometimes including pollen and nectar.” These chemicals, known as neonicotinoids, can make plants toxic to bees, butterflies, and other beneficial insects that eat pollen, sip nectar, or feed on plant tissues.

Because butterflies are insects, and products containing neonicotinoids target insects, it makes no sense to bring treated plants (or insecticides) into your butterfly haven. Always ask garden center staff if plants have been treated with insecticides (even if they are labeled “pollinator friendly”). If they don’t know the answer, don’t purchase. Additionally, organic” insecticides may not be safe for butterflies. Toxicity varies among these products. The Xerces Society offers comprehensive research information regarding both the use of insecticides containing neonicotinoids as well as organic insecticides. It should also be noted that seemingly harmless compounds sprayed on foliage (such as garlic, capsicum, or fish oil) can alter the taste or smell of foliage to the point that a plant is avoided by butterflies altogether.

“Well, I must endure the presence of a few caterpillars
if I wish to become acquainted with the butterflies.”

-The Little Prince

In the Garden It’s OK to Be Messy!
Lastly, butterflies require sheltering spaces. It’s hard for many gardeners to resist “cleaning up” their gardens in the fall. But many moths and butterflies overwinter as caterpillars, pupae, and even adults in the soil surface, leaf litter, dead plants, twigs, and other hiding places in the garden. Even log piles provide the perfect spot for some moths and butterflies to hibernate. Removing a garden’s protective layers means you may be unknowingly removing the very butterflies you are trying to attract (some pupae look exactly like leaf litter so you won’t even know you are removing them). Keep your garden’s fallen leaves, plant stems, natural debris, and hiding places intact until at least the first week of May. You will not only provide important habitat for butterflies, but other insects (the lifeblood of our ecosystem) as well. A winter garden left intact will also provide winter seeds for birds, attract wildlife, and provide visual interest for you.

It’s often easy to overlook garden visitors. Hiding in plain sight on this flower’s seedhead is the celery looper. The offspring of this moth overwinter in the soil. Disturbing the garden in the fall could prevent the next generation from emerging in the spring. (Photo credit: Dave Crawford)

“Invasive” insects aren’t the only ones chewing and chomping on your plants. All insect herbivores need to eat vegetation to survive. As says the little prince in Antoine de Saint-Exupéry’s book, “Well, I must endure the presence of a few caterpillars if I wish to become acquainted with the butterflies.” Let chewed leaves bring a smile to your face. It means you are providing a healthy habitat that will bring butterflies to your yard. Your butterfly garden will also support wildlife up the food chain—like terrestrial birds (which need thousands of insects to feed their young), reptiles, small animals, and more. To create habitat that truly welcomes butterflies, accept some imperfections in your garden plants and keep them au naturel.

Common buckeye butterfly sipping on an anise hyssop flower (photo credit: Vicki Bonk)