Milkweed Importance
Monarch Survival Depends on Milkweed
Milkweed is the lifeblood of Monarch butterflies. Although adult butterflies use other pollinator flowers for food and other plants for habitats, the lifecycle of the Monarch depends on milkweed. A female butterfly will only lay eggs on milkweed. The hatched caterpillars will only eat milkweed. Without this plant, the Monarch butterfly population would cease to exist.
Milkweed Seed Instructions
Milkweed is an upright perennial sun-loving plant. There are various types which grow to different heights, produce different colors, and have different leaf styles. It is the host plant of the nearly endangered Monarch butterfly. Milkweed likes well drained soil, but is not fussy about water and fertilization once established. Milkweed prefers full sun, but tolerates light shade.
Fall Outdoor Planting
*Recommended for All SC/US Native Milkweed*
Milkweeds seeds should be planted in the fall as the seeds need a cold period to break dormancy. Recommended spacing is 18 - 24 inches. Cover with 1/4 inch of soil. Begin watering in the spring, and water well until the seedlings are at least 6 inches tall. Slowly reduce watering as they grow. Continue to water during droughts.
Indoor Planting - Stratification
*Recommended for All SC/US Native Milkweed*
Milkweed needs a cold period to break dormancy, and the process of simulating this indoors is called stratification. Place the seeds on a damp paper towel, or on a damp soil medium, and seal them inside a plastic bag for 30 days. (Note: Western Sand requires a 60 day stratification period.) After this period, plant them in well drained nursery pots with a light source at 1/4 in depth, and keep watered. Plant seedlings outdoors after danger of frost and when seedlings are at least a few inches inches tall. Ideally, the soil temperature should be 75F or warmer. Minimize the shock of the transfer by hardening off the plants, meaning slowly increase their time outside each day in the final week before planting.
Indoor Planting - Seed Soaking
*Recommended for All Other Milkweed*
Non-native milkweed does not need the stratification process but benefits from a soaking period. Soak the seeds in warm water for 24 hours, then plant them in well drained nursery pots with a light source at 1/4 in depth, and keep watered. (Note: Swan requires a 7 day soaking period.) Plant seedlings outdoors after danger of frost and when seedlings are at least a few inches inches tall. Ideally, the soil temperature should be 75F or warmer. Minimize the shock of the transfer by hardening off the plants, meaning slowly increase their time outside each day in the final week before planting.
Germination Tips & Tricks
Milkweed germination is a slow process. If you are having trouble with milkweed germination, here are a few additional tricks to try;
- Soak the seeds in water for 24 hours before beginning the stratification process.
- After the stratification period (for native milkweed) or the soaking period (for non-native milkweed), clip the pointy end of the seed with nail clippers to improve germination rates and increase germination speed.
- Use a heat mat after the stratification or soaking process.
Milkweed Warnings
Butterfly Diseases
Native milkweed in the US is generally a perennial, but dies back each winter and reappears each spring. Milkweed varieties that do not die back should be cut back annually to prevent OE, a a butterfly disease. This is most common for the non-native milkweed varieties in warm weather climates. All milkweed is helpful for Monarchs, even tropical milkweed, as long as it is cared for properly. Cutting these varieties back each year helps manage the risk of spreading this disease.
Milkweed Toxicity
Milkweed is technically poisonous, it is part of the plants natural defense system for survival, as well as the Monarchs. This is important information to know if you plan to grow the plant, although a fairly minor concern in most cases. Contact with the milky sap can cause irritated skin and eyes. Ingestion can cause stomach upset, nausea, vomiting, abdominal pain, diarrhea, weakness, lethargy, and confusion, usually within a few hours.
As a milkweed grower, I do consider the risk low and handle milkweed on a regular basis with no concern. However, be cautious in situations where milkweed can be accessed by;
- Crawling/walking babies that like to put things in their mouths
- Young children, especially ones that like to pick flowers
- Outdoor cats, dogs & pets which may get into the flowers
- Indoor pets that are curious and/or mischievous
Milkweed species have varying levels of cardenolides, the chemical is thought to be the to cause of the toxicity. Below are a few varieties of milkweed with lower levels of cardenolides;
Common, Swamp, Butterfly & Showy
Narrowleaf, Heartleaf & California
Free Milkweed Seeds
Fire Tower Farms offers free milkweed seeds for you to help support Monarchs.
Write to us at Fire Tower Flowers and let us know why you want to plant milkweed seeds. Include a pre-addressed and stamped envelope. (We also love drawings and display them in our shop.) We will select a seed native to your area and get seeds on the way to you to help make a difference. Thank you for supporting Monarchs!
FTF Milkweed for Monarchs
469 Fire Tower Road
Prosperity, SC 29127