Monarch butterfly populations have declined by a shocking 90% over the past 20 years! One thing we can do is to plant native milkweed. Not only does it provide nectar for the adult butterflies, but also it is the only plant on which they will lay their eggs. Learn more about which milkweed varieties are best for Monarchs!
The Missing Monarchs
What has happened to our Monarch butterflies? Many factors have contributed to this horrific loss, including climate change, weather extremes, loss of winter habitat in Mexico, and widespread use of pesticides. While these are problems that will take years to change, one thing we can do in our own yards today is use less or no chemicals. A very easy thing we can do is to plant milkweed!
Not only will you help these valuable pollinators, but you’ll treasure the presence of fluttering friends in the garden!
Milkweed is the only food Monarch “babies” eat! It’s that simple. When the caterpillars hatch out, they can start feeding immediately on the milkweed leaves. Toxins in the plant make the adult Monarchs and their larvae taste bitter to predators, protecting them from hungry birds. It is such an effective deterrent that other butterflies, such as the similarly-colored Viceroy, are also avoided by predators just in case they are bitter too. If you decide to grow milkweed in your yard, be aware that the cardiac glycosides contained in the plants are toxic to pets and people also.
Milkweed Varieties
The milkweed genus (Asclepias) is fairly large, with 73 species native to the US and over 100 in North America. They support 12 species of butterflies and moths, including the Monarch. Choose ones that are native to your region and are right for your situation. Here are a few to consider; they have wide native ranges and are frequently available as seeds or plants:
Common milkweed smells so sweet they should make a perfume from it!
- Common milkweed (Asclepias syriaca) is a hardy perennial that will thrive almost anywhere in the US, especially east of the Rockies and into Canada. It needs sun, reaches 2 to 6 feet tall with wide, gray-green, velvety leaves, and is an aggressive grower. Don’t plant this in your flowerbed or it will take over. It has a wide-spreading root system and needs an area all its own, where it can really stretch out. It has pale purple-pink flowers that are very fragrant and attract many pollinators in addition to Monarchs.
Butterfly weed is a bright spot in the garden that attracts all kinds of pollinators.
- Butterfly weed (A. tuberosa) is less aggressive than its common cousin, growing only 1 to 2-1/2 feet tall. It is commonly grown in gardens, adapts well to moist or dry soil, and its orange flowers are very showy. It likes full sun and is hardy in Zones 3 to 9.
Swamp milkweed has thinner leaves and more colorful flowers than common milkweed.
- Swamp milkweed (A. incarnata) is also more well-behaved than common milkweed, forming clumps rather than spreading out. It grows 2 to 4 feet tall, has deep rose-pink flowers, and is shade tolerant. It will grow in wet soil near lakesides or damp marshlands, but also grows well in average garden soil and is hardy in Zones 3-9.
- Showy milkweed (A. speciosa) is native from west of the Mississippi into California and north to Canada. It has pastel pink flowers on 2- to 4-foot tall plants. It is drought tolerant, making it a good plant for arid plains and prairie-lands, though it grows well in moist garden soils as well. It needs full sun and is hardy in Zones 3-9.
See maps showing the native ranges of many types of milkweed.
Two No-Grows
There are some milkweeds that are not beneficial to Monarchs. Gardeners in southern states should avoid planting tropical milkweed (A. curassavica). It is a beautiful plant with bright yellow/red/orange flowers, but it hosts a parasite that infects the caterpillars and weakens the butterflies when they emerge from their chrysalis. Since the plants don’t die back until late into winter, the Monarchs stay there until it is too late to make their yearly trip to Mexico. Learn more about Monarch butterfly migration.
Black Swallow wort. If you see this growing, pull it out! (Photo from UNH Extension)
Another no-grow is climbing milkweed (Cynachum nigrum), also called black swallow-wort. It is an incredibly invasive twining weed in the milkweed family. If a Monarch lays her eggs on it, those caterpillars won’t grow large enough to turn into butterflies. It is a tough one to get rid of, since it spreads by wind-blown seeds and has a large root crown and deep roots.
Becoming a Way Station
Planting milkweed and other native wildflowers, especially late season nectar plants such as goldenrod and asters, will add to the survival chance of visiting monarchs and other pollinators by acting as an energy source and a shelter for adults, as well as host plants for larvae.
You can create a Monarch Way Station in your backyard in a 100 sq. ft. sunny space with well-drained soil. Plant at least 10 plants of two or more flower species native to your region that flower at different times, including some milkweed. Once it is up and growing, register it at MonarchWatch.org. Over 31,000 gardeners across the country have done it so far!
One reader said, “Think of it as an Airbnb for butterflies!”
Reader Comments
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TOM CHASE BUTTERFLY NATURE PHOTOGRAPH COLLECTION~
To Tom Chase: I'm pretty sure the Smithsonian Institute would want the Butterfly Collection; contact them; ty~
Tropical Milkweed
Your comments about Tropical milkweed have been found to be incorrect. Research by Jaap de Roode’s lab at Emory University, confirmed that butterflies that are infected by OE tend to prefer the tropical milkweed even more than usual. However the tropical milkweed has been found to be “medicinal” in terms of improving parasite resistance suggesting that they are self medicating their offspring. In the final analysis they determined the effect is certainly real. This is not to suggest that you should only plant tropical milkweed but some balance of the two to help them fight OE.
Milkweed - orange insects
After my milkweed matures, I find handfuls of tiny golden/orange small bugs on the leaves. Does anyone know what they are?
They are oleander or milkweed
They are oleander or milkweed aphids (Aphis nerii). They are not native to the US, coming from areas around the Mediterranean where oleander grows prolifically. They are easy to spot, bright orangey-yellow with black legs and 2 black stalks called cornicles on their back end. They can quickly form a huge colony since they do not need fertilization to reproduce and they give birth to live nymphs. Parasitic wasps will lay their eggs in them and ladybug larvae will chow down on them but to keep ahead of an infestation it is best to start squishing them as soon as you see a few.
Know all about the Monarch and gave lectures
I've photographed and gave many lectures to various Audubon Groups in NE and school kids over the years and was in conjunction with ABC TV about the Mexico winter areas. Each lecture I give info about the Monarch Watch. The "Magic Wings" butterfly place in Deerfield MA has some of my photos.
Developed many lenses to get high magnification, some pics took 4 hours to complete and developed my own 35mm color film. I know every aspect in the development of the Monarch and time frames of each stage. Was going to produced a book but my writer died and a few contacts in NYC didn't materialize. That's life. Many years were spent on this my hobby and I didn't have any Univ grants. Big bucks.
I contacted The Scientific Magazine that did a couples of articles and emailed them. No answer as usual. The article title. Search for the web site, not allowed.
Illegal logging at wintering grounds in Mexico contributes to the monarch butterfly’s decline
Have many slides about 30,000. Being 80 now, would like to disperse to a group, Audubon, etc.
It is a shame your book never
It is a shame your book never materialized. I hope you find a suitable home for your extensive collection!
No grow milkweed - help control invasive species
It would be very helpful if the article included a picture of the black swallow-wort, also known as dog strangling vine in these parts. Many people have no idea how invasive this plant is and let it grow on their fences etc. Once it is established, it's almost impossible to eradicate as every bit of root can become a new plant.
You are right Ursula. Many
You are right Ursula. Many people have no idea how invasive this plant is. Just added a picture to the article.
Tropical milkweed
Don't be so quick to give tropical milkweed a bad name. I live in central Illinios and Have grown many types of milkweed over the years. It is a pain but you must remove tropical milkweed at the end of the season and replant in the spring. It is by far the favorite of monarchs. Common milkweed is ok if you have an out-of-the way area or planting in pots as it will take over quickly. You should also mention to plant at least a dozen or so as the young cats are milkweed hogs and will die if they run out of food. Thanks, THE BUTTERFLY GUY
Thanks for that info,
Thanks for that info, butterfly guy! I think the problem with tropical milkweed is that in warm areas where it is perennial, people are not cutting it down in the late summer/fall which keeps the monarchs from continuing on their normal migration.
Coneflower Problem s
Which of the colored hybrid coneflowers have the longest life span?
I have had many of them, after 3 to 5 years they either die or maybe come back as the standard purple. I also have hundreds of purple. I live in Wi. zone 4
Thanks Tom Vanden Elzen
Planting Milkweed for Monarchs
Great idea to plant the proper species of milkweed. Thank you. Please remember to plant adult butterfly food plants nearby. The adults need food too and will stop close by the milkweed to eat. Hopefully they visit the “nursery” you have created as well. Love your daily newsletter!