Monarch butterfly numbers have become critically low in recent years, especially for western populations, which have declined by over 95 percent since the 1980s. In the east, numbers have been overall trending down from historical levels. This year, however, things are finally looking up! Numbers have increased exponentially, but we can all do a bit more to help them continue to thrive. Read on to discover how you can help to keep these beautiful insects well fed and protected.
What Caused Monarch Butterfly Numbers to Decline?
Monarch butterfly numbers have declined due to multiple factors, from the effects of climate change (such as extreme weather events and changing weather patterns) to habitat loss from agriculture and development.
The main contributing factor is the widespread use of herbicides and pesticides, which negatively impact monarchs in both agricultural and residential areas. You see, monarchs rely on milkweed to survive. It’s their caterpillars’ sole food source and is therefore a monumental factor in successful breeding. Herbicides like glyphosate eliminates milkweed from agricultural fields to devastating effect. Similarly, milkweed is generally considered a weed in residential areas. As a result, people remove it or spray it with pesticides that also hurt this crucial circle of life for the monarchs.
For these reasons, the problem became so steep that monarch populations were classified as endangered in 2023 by the International Union for Conservation of Nature (IUCN) in the U.S. and the Species at Risk Act (SARA) in Canada.
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Good News About Population Recovery
In happier news, the latest reports show that monarch butterfly populations are making a recovery. According to the World Wildlife Fund, the eastern monarch butterfly population nearly doubled in 2025. Its population wintered in central Mexico’s forests, occupying 4.42 acres: up from 2.22 acres during the previous winter. This 99 percent increase is due to better weather conditions and conservation efforts.
Things are looking up, but the number of monarch butterflies in North America are still alarmingly low. Significant challenges remain for these beautiful creatures, but we can all do our part to help them out.
If you have an outdoor space — even a small front yard or a balcony with potted plants — please consider planting the milkweed species that are indigenous to your area. Even the smallest effort will help monarch populations continue to improve.
Which Milkweed Variety Should You Plant?
How do you know which type of milkweed to plant? Look for a native species that is well-suited to your region’s conditions. Avoid tropical milkweed (unless, of course, you live in an area where it grows naturally).
Common Milkweed (Asclpias syriaca) is the best variety for monarchs in many regions. but your choice may also depend on your planting conditions. For example, choose Swamp Milkweed for moist, humid areas, and plant Common Milkweed in sunny locations.
Here are a few tips for selecting the right milkweed variety to help the monarchs in your area:
- Eastern US, Midwest: Common Milkweed (Asclepias syriaca), Swamp Milkweed (Asclepias incarnata), and Butterfly Milkweed (Asclepias tuberosa)
- Western US: Showy Milkweed (Asclepias speciosa) and Butterfly Milkweed (Asclepias tuberosa)
- Desert climates: Desert Milkweed (Asclepias subulata), Showy Milkweed (Asclepias speciosa), Butterfly Milkweed (Asclepias tuberosa), and Pineneedle Milkweed (Asclepias linaria)
- Pacific Northwest US: Showy Milkweed (Asclepias speciosa) and Narrowleaf Milkweed (Asclepias fascicularis)
- Eastern, Northern, & Southern Canada: Swamp Milkweed (Asclepias incarnata) and Common Milkweed (Asclepias syriaca)
- Western Canada: Showy Milkweed (Asclepias speciosa) and Dwarf Milkweed (Asclepias ovalifolia).
Keep in mind that there are over 100 different milkweed species, so this list isn’t a complete representation of all the options available to you. The key is finding a variety that’s native to your area.
Additionally, if you’re planting milkweed from seed, make sure the seeds are locally sourced from a reputable vendor. This ensures the plants will be adapted to your local weather conditions, and by extension, ideal for the monarchs in your area.
When in doubt, you can also double-check the milkweed variety that’s best for you by using online resources. These include the Xerces Society’s Milkweed Finder, Monarch Watch, or a native plant organization in your state.
Additional Tips for Monarch Butterfly-Friendly Gardens
Try planting other nectar-producing indigenous flower species in your garden or around your home to provide food and habitat for monarchs. The butterflies require nectar for energy to complete their migration journey from Canada to California or Mexico from mid-August through November each year. Plus, there is a wide variety of native plants that bloom throughout the season and offer monarchs a continuous food source.
Furthermore, instead of using pesticides that harm monarchs and their food sources, think organic. Use neem oil, a vinegar and water solution, or insecticidal soap instead of pesticides. Plant companion varieties in your garden and explore crop rotation to prevent pest infestations. You can also include physical barriers to keep pests out, like row covers and fences. These options are effective for small-scale pest problems around your home and are entirely monarch-friendly.
If you live in the USA, you can also register your garden space at MonarchWatch.org. By doing so, you’ll receive an official certificate and registration number as an official monarch habitat. This is ideal if your area has a homeowners association that may cause you grief in your monarch butterfly gardening efforts. You can even purchase a sign that identifies your space as a protected, registered area.
No Garden? No Problem!
Don’t have a yard or a garden? You can still help the effort by buying your produce from local or organic farms whenever possible. These sources support monarch habitats and don’t typically use pesticides.
If you’d like to get involved further, look around your community for opportunities to help researchers track monarch populations. Additionally, you can support initiatives that help conserve monarch habitats and reduce pesticide use.
No matter where you live, you can contribute. Upload photos of the monarchs and/or milkweed plants you see to the iNaturalist app or contribute to other projects on a national scale, like Western Monarch Milkweed Mapper.
Together, we can make a difference!
Stay up to date on monarch butterfly populations on the Kaleidoscope Garden website.
Photos by Joshua Cotten, Gary Bendig, and Ashlee Marie, via Unsplash Creative Commons