Just like butterflies, native moths are important plant pollinators and act as a food source for other animals. While invasive species pose challenges, the many thousands of beneficial moth species deserve their rightful place in nature and our gardens.
This guide has helpful tips for identifying the basic butterfly groups. Both butterflies and moths belong to the Lepidoptera group and play similar roles in nature.
How Moths Help Gardens
Moths are one of the many creatures in nature that deserve a better reputation.
Whether we fear them or not, moths are beneficial to gardens.
The basic test is: does this animal play a supporting role in the ecosystem? And moths most certainly do.
Some people find moths creepy or mysterious, perhaps because they associate them with chewing wool garments or furiously flapping against patio lanterns at night.
But, the fact is, they are butterfly cousins, from the same taxonomic order, Lepidoptera, and creepy or not, they are important.
Like butterflies, moths assist with pollination, need plants to sustain their offspring, and act as a vital food source for numerous other animals.
But what about destructive, non-native, invasive moths?
Yes, there are some.
If you grow brassicas like cabbage or cauliflower, you probably know cabbage moths.
Funny enough, the fluttery white ones are actually butterflies (Pieris rapae), also commonly known as cabbage butterflies or cabbage whites.
But there are also actual cabbage moth species that eat those crops including Plutella xylostella and the cabbage looper (Trichoplusia ni).
For all of them, physical barriers like these vegetable bed screens are one way to help keep cabbage pests away.
If you follow ecology news here in North America, you know the destruction spongy moths (Lymantria dispar dispar) are causing. This is a huge problem, likely exacerbated by habitat loss and climate change.
But that’s not a reason to dismiss moths as a group.
Most moth species are quietly going about their useful lives in the dark of night without us ever knowing it.
Our job as ecological gardeners is to grow the food and habitat that sustains them and all the other co-dependent players in the food web.
Contents
Frequently Asked Questions
What’s the difference between moths and butterflies?
It is not always easy to tell the difference between a moth and a butterfly. There are basic traits common to each group but there are also plenty of exceptions to these rules.
Moths Versus Butterflies
Active Time
- Butterflies are diurnal, meaning they tend to be active in daylight hours.
- Moths are often nocturnal, meaning they tend to be active at night.
Body Shapes
- Butterflies often have slender bodies.
- Moths often have thicker bodies with hair-like scales.
Wings
- At rest, butterflies hold their wings upright while moths rest their wings horizontally.
Antennae
- Butterfly antennae are often slender with bulbs or clubs on the tips.
- Moths have feathered or saw-edged feelers or antennae.
Are moths good or bad?
A useful measure of “good” or “bad” in nature is whether a plant or animal plays a supporting role in the local ecosystem. Native moths most certainly do both as a food source for other animals and as a plant pollinator.
The exception is invasive, non-native species that cause harm. One example here in North America is the LDD moth or Lymantria dispar dispar (common name spongy moth, formerly gypsy moth) that poses a great threat to oaks and other species of trees.
Do moths sting or bite?
Moths do not sting or bite or pose any other threat to humans.
Do all moths eat clothes?
No, there are over 150,000 species of moths worldwide and very few of them eat clothes. For those that do, it’s actually the larvae that chew the fibers, not the adult moths. While some species will make holes in wool garments, they are not likely to eat cotton or synthetics.
What are some moth predators?
Animals that eat moths include birds, bats, lizards, dragonflies, rodents, frogs, and some spiders.
What do moths eat?
Most moth species are herbivores.
- As larvae or caterpillars, moths eat plant leaves.
- As adults, moths consume sap or nectar.
- There are also some carnivorous moths that, either during the larval or adult phase, eat other animals like snails or insects.1
- Some adult moths do not have mouthparts and cannot eat. These species live just long enough to reproduce over a few days.
Are moths pollinators?
Yes, moths are pollinators. While bees may be our most prolific pollinators, nocturnal pollinators including moths are also vital to our ecosystems. This explores various other pollinators including insects, birds, mammals, and lizards.
A recent study published at plos.org found pollen deposition rates by moths at night were greater than those by bees by day.2 Another study published by The Royal Society found moths can find pollen sources that bees overlook.3
Just a few of the plants moths pollinate include phlox and salvia species. Some moth species (Schinia felicita and S. florida) are completely reliant on evening primrose (Oenothera).
How do moths support biodiversity?
One way moths help support biodiversity is through their ability to carry pollen over greater distances than butterflies can. While not all moth species do this, when it happens, it helps distribute genes (via the pollen) over broader areas.
How long do moths live?
The life cycles vary by species but generally, most of a moth’s life is spent as an egg, larva, and caterpillar prior to metamorphasis. The adult phase can be relatively short, lasting just days or weeks. One example is the Luna moth or American moon moth (Actias luna) that lays its eggs on broadleaf trees including hickory, sumac, and walnut. In some climates, adult Lunas have just one generation per year. Active only at night, it’s quite a treat to see one.
Related: Should I use bt (Bacillus thuringiensis) to get rid of caterpillars?
What are some interesting characteristics about moths?
Moths have evolved over time disguising their appearance to deter their predators.
Some camouflage so effectively they disappear into their surroundings, blending into bark or leaf litter.
You’ve probably seen photos of moths like the Polyphemus moth (Antheraea polyphemus) that appears to have giant eyes on its wings. That’s quite a way to startle a predator!
Others, like clearwing moths (Hemaris thysbe) mimic hummingbirds flitting about the garden.
How many moth species are there?
| Worldwide | North America | |
|---|---|---|
| Moth species | 150,000 | 12,000 |
| Butterfly species | 18,500 | 750 |
There are approximately 150,000 moth species worldwide and 18,500 butterfly species.
Within North America there are 12,000 identified species of moths and approximately 750 butterfly species.
Are butterflies more colorful than moths?
While some butterflies definitely have clearer, brighter colors and patterns, there are plenty of bold-looking moths as well. I highly recommend browsing the photos at the Butterflies and Moths of North America website to see the incredible diversity.
Moths & Lights
While moths appear attracted to artificial lights at night, recent research indicates they are actually disoriented—sometimes at their peril. They gain no benefit from flapping at a light, wasting precious energy they could be using for food collection or reproduction. Unless specifically using lights to trap and study moths, darkness is best.
This explains how light pollution negatively affects wildlife.
How to Attract Moths
The tips for attracting moths begin with the same things that support all the other living things we want in an eco-beneficial garden.
Both butterflies and moths undergo metamorphosis to reach adulthood. The life cycle includes eggs, larvae, and then caterpillars which eventually pupate. For years gardeners have been taught to hate caterpillars because they eat plant leaves. Once you realize that’s their only food source, suddenly, instead of resenting the plant damage, we realize the system is working exactly as it should.
Grow a diverse selection of plants, trees, and shrubs that support local wildlife.
For moths, learn which plant species they rely on for egg-laying and those that provide nectar for adults.
Avoid bug zappers. They don’t just zap mosquitoes.
Keep old tree stumps, leaves, and branches to provide lots of nooks and crannies—not just for moths but all the animals that need them for habitat.
Convert dead zones like manicured lawns, concrete slabs, and gravel beds to garden beds with beneficial plants, trees, and shrubs wherever possible.
Provide a source of fresh water.
Reduce light pollution. If you need lights for safety, choose yellow-colored bulbs, not white.
Accept that today’s caterpillar is tomorrow’s moth or butterfly. Larvae and caterpillars have to eat plant leaves to survive. If you see chew marks on leaves, you’re on the right track.
Resources
More About Moths
- Butterflies and Moths of North America (Bamona) | website with photos
- Peterson Field Guide to Moths of Northeastern North America | book
Listen
Footnotes
- Killer Caterpillar Eats Snails Alive | livescience.com
- Marvellous moths! pollen deposition rate of bramble (Rubus futicosus L. agg.) is greater at night than day | journals.plos.org
- Moths Work the Pollination Night Shift, Visiting Some Flowers Bees Skip | smithsonianmag.com
About Cabbage Moths
What we often call “cabbage moths” are actually butterflies (Pieris rapae)—they are the white, fluttery ones you’ll see scoping out your brassicas.
There are also (brown-ish) moth species we call “cabbage moths.”
This includes the diamondback moth (Plutella xylostella) and
the cabbage looper (Trichoplusia ni) which you’ll also see around cruciferous vegetables.
I hope this has encouraged you to learn more about moths and make a healthy ecosystem top priority in your garden. And, if you have room, add pond for native frogs and toads.
~Melissa the Empress of Dirt ♛