Tropical milkweed cuttings can be started indoors throughout the year, but native milkweed has a smaller window of opportunity…
Summer is a prime time to take native milkweed cuttings for a few compelling reasons:
- native milkweed plants still have herbaceous, viable stems
- mid-summer cuttings will grow roots in plenty of time for fall planting
- You can keep the cuttings containers outdoors
Here are some milkweed varieties we will attempt to propagate with stem cuttings, but really, you can try this with any variety if you have herbaceous stems available:
Tuberosa is one of the few varieties that can be propagated in both soil and water. We’ve attempted to root other native milkweeds in water, but the stems have always rotted.
For the following varieties (and others not listed) we suggest using the traditional cloning method detailed below:
Steps for Taking Native Milkweed Cuttings
1. Use organic peat or all-purpose potting soil in pots.
1a. An alternative idea is to place cuttings in 2 liter soda bottles to give each cutting optimal growing conditions in their own mini-greenhouse.
2. Mix in perlite or coarse sand to allow more air to reach the newly forming roots
2. Water soil thoroughly.
3. Insert chopstick/pencil in soil to make holes for placing cuttings.
4. Use a sharp hand pruner to take cuttings.
5. Take a cutting that has between 3-5 leaf nodes (or is about 4″ long).
6. Pinch off all but the top two pairs of leaves from your cuttings so that water doesn’t evaporate through the leaves…transpiration.
7. Scrape the bottom third of the cutting with a sharp knife.
8. Dip the scraped area in rooting hormone powder. Find several options and customer reviews here:
9. Place cuttings in holes and secure soil around them.
10. Keep cuttings in an area that receives light, but minimal direct sunlight.
11. Spray soil and leaves daily.
Soil For Cuttings
We’re planting our native milkweed cuttings in an 80/20 mix of perlite to peat moss, which is a more traditional mix for starting stem cuttings than starting in soil.
Adding sand and/or vermiculite to the mix could also increase your success rate for milkweed cuttings.
In previous seasons, we tried starting milkweed cuttings in potting soil and most of the cuttings rotted because there wasn’t enough oxygen in the soil. If you opt for potting soil as your growing medium, be sure to mix in plenty of perlite…
Alternatively, you could direct planting your cuttings in regular garden soil using rooting hormone powder. We’ve done this successfully with tropical milkweed, but have not tried with other native or non-native varieties.
Unfortunately, we have not had much success with native milkweed cuttings. Your best chance for cloning is with Asclepias tuberosa. Asclepias incarnata can be easily divided in spring/fall to multiply your milkweed supply.