I absolutely love milkweed. When the towering stalks pop up each summer, I get to watch my garden turn into a monarch butterfly paradise!
Milkweed is a central feature in my garden, and I want to make sure it has everything it needs to come back in the spring.
Luckily, there isn’t all that much that you need to do – though there are a few tips and tricks that you should follow to ensure the perennial growth of healthy plants with an abundance of blooms.
We link to vendors to help you find relevant products. If you buy from one of our links, we may earn a commission.
If you’re just getting started, you can find complete cultivation instructions in our growing guide.
Read on to learn how to care for Asclepias plants during the winter, so they can return robust as ever the following spring.
What You’ll Learn
Winter Care
Milkweed is an herbaceous perennial, and the Asclepias genus includes more than 100 species native to the US and Canada.
These can be identified by their characteristic milky white sap, which can be found within the stems and leaves.
Plants in this genus flower during the summer, set seed in the fall, and die back in winter.
With proper care, they’ll be ready to sprout again the following spring from an underground network of creeping roots. Milkweed also spreads easily from seed.
There are species that have adapted to grow in almost all climates. If you are growing a variety that is native to your climate, winter care requirements will be minimal.
If you live in a cold climate or you are growing a species that isn’t quite hardy to your zone, you can add a few inches of wood chips or straw mulch to help protect the root system over the winter.
You can find our list of recommended milkweed varieties here.
Prune in Fall or Early Spring
You can cut plants back in the fall or wait until the spring.
If you hold off until early spring, this allows birds and other small animals to use the fluff surrounding the seeds and the fibers from the stalks to build nests.
To prune, just use a pair of clean pruners to cut each dead stem to the ground. These can be added to the compost pile.
Whenever you choose to prune, just make sure to wait until the seed pods have matured and dispersed their seeds first.
Save and Spread Seeds
Milkweed plants are the main food source and habitat for monarch caterpillars, an important and threatened native pollinator – so the more we can spread it around, the better!
Seeds from some species require cold stratification, so if you let the seeds disperse they will sit dormant in the garden until spring. Warm weather and tropical species including A. curassavica do not require cold stratification.
You can also collect them and spread them out yourself wherever you want them. Do this in late fall, after the first frost but before a hard freeze.
Butterflies Galore
Caring for milkweed in winter is a piece of cake, and the rewards are so satisfying! With barely any effort required over the winter, you can watch your garden fill up with a huge patch year after year.
First will come the caterpillars, then enchanting glasslike cocoons will hang down from the branches, and finally the garden will be filled with butterflies!
What are your tips for overwintering milkweed? Share your thoughts in the comments below!
And for more tips on preparing your flowers for winter, check out these guides next:
- How to Prepare Your Delphinium Plants for Winter
- How to Care for Peony Plants in Winter
- How to Prepare Coreopsis for Winter
© Ask the Experts, LLC. ALL RIGHTS RESERVED. See our TOS for more details. Uncredited photos: Shutterstock.
Heather, I am going to mass plant a plot of land on our farm with common milkweed along with bulk pollinator seed.I am starting with a grassy [lot of land. Though it has been bush hogged, there is a thick growth of grass and weeds. I plan to cover the space with tarps for two weeks.
If I am able to “lasagna garden” over cardboard or thick newspapers, I plan to create a 2′-3′ layer of composted materials and soil. Do you have any advice for me?
Zone 7, NC
Thanks!
Hi Ann, It sounds like your plan to cover with tarps and then “lasagna” garden over newspaper or cardboard is a good one. I would recommend a thicker layer of material above the newspaper if you can. A couple of feet total is generally recommended for best results. You an include layers of whatever organic matter you can get your hands on; straw, compost, aged manure, leaves, grass clippings, etc. and top off with a layer of soil that can be easily seeded. Since milkweed requires a period of cold stratification, it is best to either seed in late fall… Read more »
I’ve planted a small patch of milkweed in my garden near other plants, specifically an Althea/Rose of Sharon and Crape Myrtle. I anticipated pollinating butterflies but didn’t think about the cocoon/caterpillar stage. I’m concerned about them damaging the other plants. Will they just prefer the milkweed or do you have any suggestions on containing them?
Hi John,
Good question! I wouldn’t worry too much about milkweed leading to damage for other plants. Monarchs in particular are only interested in milkweed, and in general milkweed also attracts a variety of predatory insects and pollinators that are helpful to keeping pests in check and the whole garden healthy!
Where can I find free milkweed seeds? I am in Illinois and I want the milkweed that is the foundation for egg laying for monarchs. I believe they are the fluffy milky seeds that pop out every fall.
Does it get to 32 degrees or lower where you live? I am asking because I planted tropical milkweed here in the low desert of AZ. Not a good thing here because it doesn’t go dormant here and can lead to a parasite that can grow over the winter on the plant here and can harm monarchs. I have many plants I will cut to the ground in Dec. to prevent the parasitic growth. I have collected seeds from this plant that I willing to share with people in States that actually get a real winter.
You can easily find and collect milkweed seedpods in the fall in fields, prairies, and other open areas. It is a good idea to know your local laws on collecting seeds on public or private land, and to be sure you correctly identify the plant.
If you can’t find any locally, there are lots of places to purchase seeds, such as these organic common milkweed seeds from Botanical Interests.
Look up live monarch foundation seed is sold via donation
Is it normal for milkweeds to turn brown in winter? Or am I not watering the right amount?
Yes, this is normal. Milkweed is a perennial that dies back in winter in most climates, and will grow again in spring from a network of creeping underground roots. No need to water in winter.
So I am just getting started and locating your info on which seeds are best for Oregon. What worries me is the birds. Won’t they come after the larvae or butterflies? We have some very determined birds and tons of dreaded starlings. Any suggestions would be appreciated. Thanks, Nora
Great question, Nora. Monarchs have their own built-in defenses against predation, thanks in part to their choice of host plant. Chowing down on milkweed actually provides protection for the larvae! And those brightly colored stripes and wings also serve as a warning to local vertebrates that says “do not eat me.” Birds will often turn to milkweed for nesting material, if the seeds and stalks are left in place over the winter. But milkweed contains toxic cardiac glycosides that will often cause birds and other animals to vomit and avoid that unpleasant food source in the future without causing any… Read more »
Thanks Allison, I am hoping with butterfly bushes, rhodys, azaleas, fox glove, passion flower, wisteria, honeysuckle, hollyhock and assorted berries should give them, bees and humming birds a bit to hold them over. But, with the starlings, there is not much that deters them…sure wish they had stayed in England. Could you tell me which of the milkweed produce the most toxin that I could use in Oregon? Thank you, Nora
Sounds like a wonderful assortment! Where are you located in Oregon specifically? USDA Hardiness Zones there range from 4b to 9b. Heartleaf (Asclepias cordifolia) and showy (A. speciosa) milkweeds are native there, and the latter may be your best option as it produces narrow leaves and grows across a broader range into areas with colder winters. See our guide to varieties of milkweed for more detail on both of these species. It’s tough to say specifically which might be the most productive. According to a report from the Agricultural Research Service at the USDA, “Labriform milkweed (A. labriformis) is the… Read more »