Bloodflower Tropical Milkweed Seeds

Bloodflower tropical milkweed is a beautiful plant for your flower garden that attracts and feeds butterflies! This tender perennial can be grown year-round in mild areas of Southern California. Butterflies seek it out as a food source. Cut back the plant when it begins to look ragged in the fall or winter.

Planting by Zones

Zones 9-10

• Bloodflower or tropical milkweed is a warm-season flower that may be planted into the ground once the soil has warmed up to at least 65°F. Blooms from early spring and well into the fall. Grown as a perennial in mild areas of Zones 9 and 10.

Zones 2-8

• Grown as an annual in cooler climates. Plant in the spring after the danger of frost is gone.

Planting Tropical Milkweed Seeds

• You can choose to direct sow seeds in a weed-free area of your garden or plant them in starter pots and transplant them outside. To direct sow, plant seeds in debris-free, well-worked soil that has been deeply watered. Cover with 1/4″ of finely sifted soil. 
• If you are planting seeds in starter pots, plant seeds into thoroughly moist high-quality seed starting soil. Place seeds on top of the soil and cover with 1/4″ of finely sifted soil. 
• Once your seeds have germinated and the first set of true leaves show, fertilize with an organic liquid fertilizer. Plant out into the garden when they reach 3-4″ tall.
• Plant in full sun, in moist, well-draining soil.
• Space 16-24″ apart. Plants grow 3-4″ tall with a spread of about 2 feet. 

Growing Tropical Milkweed

• Plants are drought-tolerant and do not require a lot of care once they are established. Tropical milkweed easily reseeds.
• Mulching heavily around your plants will help with weed suppression and moisture retention.
• Be sure to plant enough tropical milkweed to sustain the monarchs! Monarch butterflies lay eggs on the plant in early spring. Once hatched, the caterpillars consume huge portions of milkweed as they prepare for adulthood. 

Growing Tropical Milkweed in Containers

• If you are planting tropical milkweed in containers, make sure your container is at least 20″ deep. Keep in mind containers will dry out faster because they have more surface area and less soil to hold onto moisture.  

Harvesting Tropical Milkweed Flowers

• Tropical milkweed is commonly grown as a host plant for monarch butterflies. We recommend letting flowers stay in the garden. Hummingbirds, bees, and beneficial insects love it too!

Southern California Pro-tips

• Tropical milkweed should be cut back to the ground in late fall, in areas with mild winters where plants do not die back naturally. Doing so limits the spread of parasitic disease in monarch butterflies and encourages them to overwinter according to their natural migratory pattern. Plants that have been cut back will grow back in time for spring!

Companion Flowers/Crops

• Tropical milkweed is a wonderful addition to butterfly gardens. Other butterfly host plants include Florence fennel, Finale fennel, and narrowleaf milkweed. Shop all our flowers here.

Additional Learning Resources

• New to starting crops from seeds? Please watch our Seed Starting Presentation to learn the basics!
• Learn about growing all our crops on our YouTube page!
• Having pest issues? Check out in-depth information on garden pests at the UC Integrated Pest Management site.