The days are growing increasingly shorter and the nights cooler and cooler: autumn is really and truly here. For some people, that means beautiful days in orchards picking apples, or in the fields harvesting pumpkins. But were you aware that it’s also a terrific time to harvest milkweed fruits? This is not only an interesting time to carry out Monarch Missions, but it’s also a great opportunity to get your hand on some milkweed seeds in order to create breeding habitats1 for the monarch!
The best time for harvesting milkweed follicles
Generally, milkweed follicles (fruit) reach maturity in October. At that point they’re brownish in color and open (see photo 1), revealing seeds with silky plumes. If the seeds have already started to disperse by themselves it will be more difficult to harvest them, so it’s preferable to harvest the fruit before they reach that stage.
Look for greenish (or slightly brownish) fruit whose seam is still closed, or barely open (see photo 2). Press the follicle gently to open it (sometimes you’ll hear a slight “pop”) and look inside: if the seeds are dry and a caramel color, it’s the right time to harvest them. However, if the seeds are white, or if the seam doesn’t open, it’s best to leave the follicle a few more days on the plant.
Be careful when harvesting fruits!
In nature, you have to make sure to properly identify milkweed species before harvesting their fruit. If you come across common milkweed (Asclepias syriaca) or swamp milkweed (Asclepias incarnata), then go right ahead. Bear in mind, though, that it’s preferable not to harvest all of it so that the wild populations can regenerate naturally.
On the other hand, if you find some butterfly weed (Asclepias tuberosa) or poke milkweed (Asclepias exaltata) in the wild, none of these may be harvested, as they’re protected under the Québec Act Respecting Threatened or Vulnerable Species.2,3 To correctly recognize the various types of milkweed, consult our Milkweed species identification sheet.
It’s also possible to harvest fruit in town ‒ in gardens, parks, or even vacant lots. But make sure you have permission to enter the site before you start gathering the fruit!
How to manage seeds?
Now that you’ve got your milkweed fruit, the seeds have to be removed. The first step is, gently take the compact mass of fluff and seeds from its follicle (see photo 3). Next, firmly pinch the tip of the fluff mass and scrape the seeds off with your thumb (see photo 4). The seeds should separate easily from their plumes. To keep seeds from spoiling it’s important to let them dry out on paper towel or a piece of cardboard in a cool, dry place for about a week.
When to sow?
It’s up to you! In the fall you just have to plant the seeds wherever you want before the first frost. If you’d rather wait until the following spring, you’ll have to think about stratifying the seeds before sowing them. That simply means exposing them to cold in order to help them germinate. To do that, place the seeds in a plastic bag with paper towel, or with sand (damp but not soaked), and put the bag in the refrigerator for at least 30 days. Your seeds will then be ready for sowing.4
Enjoyable and useful both
This activity fits in perfectly with the Mission Monarch program. Whether it’s through harvesting your follicles in the autumn or by monitoring the emergence of your plants the following spring, you can carry out a Mission Monarch and submit your findings. Even if the monarch isn’t there itself, your milkweed observations are important!
To find out more:
3Québec act respecting threatened or vulnerable species (in French only)