Fall planting is a great way to get your perennial milkweed varieties started, since the seeds will need cold stratification…and Father Winter takes care of this naturally! Consider planting milkweed varieties that are native to your region for best results.
Why is fall planting milkweed a good idea? Exposing seeds to cool temperatures before the warmer temps of spring will cause them to break their dormancy coaxing out your new spring seedlings. It also saves you the hassle of in-home stratification.
Warm weather milkweeds, which are annuals for most of us, do not require this cold treatment. These varieties include tropical milkweed, swan milkweed, goose plant, and giant milkweed.
If you still need to collect milkweed seeds from your garden or local milkweed patch, check out this article to how to harvest milkweed seeds.
If you are buying seeds from a vendor, they should have instructions telling you whether cold stratification is necessary. If not, search for specific milkweed pages on this site or consult with Mother Google.
10 Simple Steps for Fall Planting Milkweed
1. Put your seeds into a small bowl and bring out to planting area. Find seeds here if you still need to buy some.
2. Clear away any mulch or rocks from the area which could potentially block the growth of a small seedling.
3. Water the area thoroughly and let it saturate the soil.
4. Put on garden gloves and stick your index finger in the dirt up to your first knuckle.
5. Repeat this process for each seed you are planting.
Measuring between holes: Make the letter L with your thumb and forefinger. Use the distance between the tips of each digit for approximate spacing. Seeds can move over winter and some won’t germinate so exact spacing now is a waste of time.
6. Place a seed in each hole.
7. Cover the seeds with the already-moist soil. You can place a few inches of straw or leaf mulch over the area to keep the soil from drying out.
8. Mark your seeds with sturdy plant labels.
Be sure to use a weatherproof garden marker (intended for outdoor use) so your labels don’t rinse away over winter.
9. SQUIRRELS? Consider putting down chicken wire to deter squirrels or other pesky critters from digging up your new milkweed patch. You could also put off planting until just before the ground freezes or before your first major snowstorm.
10. Relax for the winter.
11. 1-2 months after your seedlings have sprouted next spring, pinch off extra plants (or consider transplanting) to achieve ideal spacing for your specific milkweed. The Ascelpias viridis (spider milkweed) plants will be spaced 1.5 to 2 feet apart.
If you miss the window of opportunity for fall planting, winter sowing milkweed seeds is also an option.