Gather the butterfly weed seeds in late summer or autumn, once the pods dry to a light, rosy-beige color, but before they split open. Put on rubber gloves before handling the pods to protect your hands from the mildly toxic sap.
Butterfly weed and milkweed seed pods may be harvested and planted to support Monarch butterfly caterpillars. Butterfly weed grows well from seeds, which must be harvested in late summer and either sown immediately in the garden, or started in spring after a lengthy chilling process. The seeds are viable and will germinate with little care, although they must be planted at the appropriate depth to ensure successful sprouting.
Place the butterfly weed seeds in a plastic bag filled with 1 cup of moistened perlite. Store the bag inside the refrigerator for three months. Mist the perlite with water every few days to keep it from drying out completely.
Before you begin to harvest the butterfly weed pods, sterilize your cutting tools. Dip the blades into a full-strength household cleanser, such as Lysol or Pine-Sol. Repeat between cuts to prevent the spread of diseases.
Make a 1/4-inch-deep planting hole in the center of compost mixture. Drop one butterfly weed seed in the planting hole. Cover it with a loose layer of compost. Mist the compost to settle it.
Typically, the easiest and most successful way to add Butterfly Weed to your garden is to grow it from seed form. Plant fresh seeds in fall for growth the following spring, or allow any established Butterfly Weeds already in your garden to do the work for you. Beginning in late summer or early fall, the plants should start to develop seed pods in place of their blooms. If left on the stem, the pods will eventually burst and the seeds inside will be blown throughout your garden, allowing them to establish themselves in the soil in time for the following year. If you’d rather have more control over the eventual location of any new Butterfly Weed plants, you can remove the seed pods from the plant before they burst open and simply plant new seeds by hand instead.
During its first year of life (or until new plants start showing mature growth), you should maintain a moist soil environment for the Butterfly Weed. Once the plant appears to be well-established, you can cut back to watering it only occasionally, as it now prefers dry soil.
The low maintenance Butterfly Weed does not require any additional fertilization—in fact, doing so can harm the plant, so it’s best to just let it do its thing.
How to Grow Butterfly Weed From Seed
Butterfly weed is a must-have plant for green thumbs looking to coax its namesake beautiful winged insects into their garden. Also known as Asclepias tuberosa, orange milkweed, pleurisy root, and yellow milkweed, the plant can grow to be anywhere from one to two feet tall and is characterized by glossy green leaves and clusters of bright orange-to-yellow blooms that are rich with nectar and pollen, which in turn attracts butterflies, along with bees, insects, and hummingbirds, all summer long. First grown in the prairies of the Midwestern United States, Butterfly Weed boasts a long medicinal history as well—Native Americans used to chew the roots as a remedy for pleurisy and other pulmonary issues, and they can also be brewed into a tea that can then be used to treat diarrhea and other stomach ailments. Butterfly weed should be planted in the early spring (after the final frost)—it will be slow to emerge, but will grow quickly once it does, hitting peak height and bloom in mid-to-late summer.
Though considered non-toxic, the roots and sap from Butterfly Weed can cause vomiting, weakness, and spasms in both animals and humans if consumed in very large quantities.
Choose a spot in your garden to plant your Butterfly Weed that boasts hours of bright sunlight daily, as this plant loves to soak up the rays. Full-sun is definitely your best bet, but the hardy plant can tolerate a few hours of shade too.
Because the Butterfly Weed is adaptable to zones three through nine, it can thrive in a variety of different temperature and humidity settings. Generally, the plant emerges in late spring, hitting its peak bloom during the warmer summer months and drying on the stem throughout the autumn and winter. It also tolerates heat and drought well.