How To Grow Milkweed Plants
Asclepias - also known by the common name Milkweed or Butterfly Weed - is a beautiful North American wildflower and a delightful garden plant. Fragrant clusters of flowers are a magnet for butterflies and pollinators - and a delight for the senses!
The leaves of all milkweed species are the host plant for the caterpillars of beautiful American monarch butterflies - meaning milkweed leaves are the ONLY food that they can eat to survive. Fortunately, you can plant milkweed to help support your local monarch butterfly and pollinator population!
With a wide native range from the eastern seaboard to the Rocky Mountains, including southern Canada, these plants thrive in a wide range of garden and meadow habitats and help to provide much-needed habitat for monarch butterflies, bees, and other pollinators.
Follow our guide to learn how to plant and grow healthy milkweed plants!
Choose Your Milkweed Plants
At American Meadows, we offer Milkweed for every yard!
- Common Milkweed (Asclepias syriaca) is highly adaptable species with a wide native range that covers most of the eastern US, most of the Midwest, and Southern Canada. It grows well in most soil types garden soil. It’s known for its large globes of pink flowers.
- Swamp Milkweed (Asclepias incarnata) will do best in a moist environment, making it a great option for wet meadows or rain gardens. Its common name refers to the swampy environments of the meadows where it thrives.
- Butterfly Weed (Asclepias tuberosa) is well suited for dry and sandy soils. Butterfly weed is known for its bright orange flower clusters.
- Showy Milkweed (Asclepias speciosa) is native to drier regions of the western US and serves as a major food source for Western monarch caterpillars.
Shop Milkweed Plants
When & Where To Plant Milkweed
Light: Plant in full sun locations. Milkweed plants need plenty of light as they grow.
Spacing: Milkweed plants establish large, deep root systems and prefer not to be transplanted. In the right conditions, milkweed plants can spread aggressively by runners, or by reseeding. If you want them to naturalize and spread to increase habitat, then give them plenty of space to expand.
- Butterfly Weed, Whorled Milkweed, and Common Milkweed should all be spaced about 18” apart.
- Swamp Milkweed eventually matures to forms clumps up to 36" across. You can plant them closer and thin the plants as they grow in, or, plant Swamp Milkweed and its cultivars between 30” and 36” apart.
Plant low-growing perennials in front of the milkweed, as they’ll hide the spindly stems once the flowers have passed or once leaves have been eaten by Monarc caterpillars. You’ll still be able to see them bloom, as the caterpillars don’t eat up to the flowers.
Planting Time: Milkweed plants can be planted in spring or fall.
When planting in spring, your milkweed plants will likely arrive in a dormant state, with no green leaves above the soil line. This is perfectly normal! Milkweed can be slow to wake up from dormancy compared to other perennials in your garden. These plants tend to wake up in late spring or early summer. Your plant will wake up from dormancy as the soil warms, and then you should begin to see leaves form. Be sure not to overwater while they are dormant.
How To Plant Milkweed: Step-By-Step Instructions
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Start with healthy plants that have developed root systems.
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Prepare a planting hole that's twice as deep and twize as wide as the root ball of your milkweed plant. When planting multiple plants, you can amend the soil for each planting hole, or amend the whole bed before planting.
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If the roots are clinging to the sides of the pot, you can "rough up" the roots to encourage outward growth.
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Plant your lmilkweed with the top of the root ball even with the soil line. Backfill soil around the plant and press firmly all around.
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Water well to compress the soil and remove an air pockets.
How To Care For Milkweed Plants
Growth habit: The plants typically form clumps. Plant it in a suitable place in your garden where it won’t invade your lawn or overcrowd other plants.
Staking: Milkweed plants have sturdy stems - no staking needed. They may flop when they don’t get enough sunlight.
Watering: Swamp Milkweed and Tropical Milkweed varieties need either a naturally moist environment or regular watering. Whorled Milkweed, Common Milkweed, Showy Milkweed, and Butterfly Weed are suited to a dry environment.
Fertilizing: Milkweed does not require fertilization. This native plant performs well in poor soils.
Mulching: Mulching is typically not recommended for Milkweed plants.
Trimming & Pruning: None needed during the season.
End Of Season Milkweed Care
Dividing & Transplanting: All Milkweed, and Swamp Milkweed in particular, develop a deep tap-root, so we do not recommend dividing or transplanting milkweed plants once they've been established in your garden or meadow.
Milkweed will naturally reseed and spread over time. You can harvest the seeds to plant them where you'd like, or, remove the seed pods in early fall, before they split open and spread their seeds.
Pests & Disease: Typically there are no serious pests or diseases that affect mature milkweed. In certain situations, aphids or whitefly can overrun your milkweed plants. Use a jet of water to hose them off. When you spray, be sure to avoid any clusters of Monarch eggs that are growing on the affected plants. Move any Monarch larvae that have already hatched to a clean place before spraying.
