10 Major Types of Milkweed Varieties

Milkweed is a genus of herbaceous, perennial flowering plants that grows to heights of between 2 to 6 feet on solitary stalks. Milkweed gets its name from the milky sap contained in its leaves and stems. Milkweed can be found in a wide range of habitats including roadsides, fields and gardens. The leaves of Asclepias species are food source for Monarch butterfly larvae and some other milkweed butterflies. Milkweed plant varieties are often used in butterfly gardening and monarch waystations. There are numerous varieties of milkweeds, here are 10 common varieties.

1. Swamp Milkweed (Asclepias Incarnata)

Swamp milkweed also referred to as rose milkflower or white Indian hemp grows approximately 40 to 60 inches tall. Its stems are branched and the clump forming plants emerge in late spring after most other plants have begun growth for the year. This plant bloom in early to mid-summer, producing small, fragrant, and pink to sometimes white colored flowers in rounded umbels.

Swamp milkweed grows in damp to wet soils and also is cultivated as a garden plant for its flowers, which attract butterflies and other pollinators with nectar. After blooming, the plant produce green seed pods that split open when ripe releasing light to dark brown, flat seeds.

2. Oval-leaved Milkweed (Asclepias Ovalifolia)

Asclepias ovalifolia also referred to as oval-leaved milkweed grows to 8-20 inch tall. Its central stem is light green to brown and has opposite leaves that are oblong or elliptic shaped occurring at intervals along the un-branched central stem. The upper surfaces of the blades are green and hairless, while their lower surfaces of the blades are pale green and canescent to short-pubescent.

The flowers of oval-leaved milkweed species are white and produced in several umbels. This plant blooms in early to mid-summer and like most milkweeds, this species is monoecious and produce sap in its tissues. Oval-leaf milkweed is one of the very few woodland milkweeds that grow with morning sun and afternoon shade or filtered sun all day long.

3. White Swamp Milkweed (Asclepias Perennis)

Asclepias Perennis also referred to as White swamp milkweed grows to between 1 and 2 feet tall consisting of a cluster of un-branched flowering stems that are light green to purplish in color. Pairs of leaves occur on the stems at fairly frequent intervals along the stems. The upper leaf surface is medium to dark green whereas the lower leaf surface is light to medium green.

The blooming period occurs from late spring to mid-summer, lasting about 1-2 months. The flowers are mildly fragrant. Both the leaves and stems of white swamp milkweed contain a milky latex and its pinkish white flowers attract butterflies and other pollinators and its foliage is larval food for both Monarch and queen butterflies.

4. Purple Mikweed (Asclepias Purpurascens)

Asclepias Purpurascens also referred to as purple milkweed, gets its name from flowers that first develop a pink color but then turn darker purple as they mature. Purple milkweed looks similar to common milkweed but the flower color is rich red-purple color compared to the soft gray-pink of common milkweed. Its seed pods are smooth and a little more slender than those of common milkweed which has plump pods with a prickly surface. Also purple milkweed tends to spread less aggressively than other milkweed species.

The best time to view this beautiful and special wildflower is from June to August. The blooms occur in the upper leaf axils of upright stems clad with thick, oval, dark green leaves, adorned with pointed tips. Its flowers are a great source of nectar for butterflies, hummingbirds, bees and other beneficial insects. After blooming, the plant produce green seed pods that split open when ripe releasing seeds with long, silvery-white, silky hairs.

5. Common Milkweed (Asclepias syriaca)

Asclepias syriaca commonly referred to as common milkweed, butterfly flower, silkweed or Virginia silkweed can grow up to 10 feet tall usually occurring in clusters of stout stems. It has rhizomes and quickly forms colonies. Within its range it can be found in a broad array of habitats from croplands, to pastures, roadsides, ditches and old fields.

The stem of common milkweed has simple, oppositely arranged leaves of up to 8-inches long and 3½ inches wide, oblong in shape and smooth along their margins. The upper leaf surface is pale-medium to dark green and hairless above whereas the lower leaf surface is densely covered with short wooly hairs.

Extremely fragrant, umbels of flower clusters emerge from the axils of the upper leaves. Flowers range in color from faded pink to reddish-purple.  The flowers of common milk weed bloom for several weeks in July and August.

6. Butterfly Milkweed (Asclepias tuberosa)

Butterfly milkweed also referred to as Asclepias tuberosa grows between 2 and 3 feet tall, with clustered orange or yellow flowers from early summer to early autumn. The stems are light green to dull reddish purple and less covered with spreading hairs. The root system of this plant consists of a woody taproot that is thick and knobby. The taproot can extend several feet below the ground surface.

Mature seeds of butterfly weed are about 4 mm long, flattened along margins; the apices of these seeds have large tufts of white hair. The plant grows well in full sun, mesic to dry conditions and in acidic soil that is sandy or rocky.

7. Wheel Milkweed (Asclepias Uncialis)

Asclepias uncialis also referred to as Wheel milkweed grows between 2 and 6 feet tall. The stems are light green to dull green and less covered with spreading hairs. The lower leaves are lance-shaped to oval whereas the upper leaves are narrower.  The flowers occur at the ends of the stems in clusters of up to 12. They are pinkish purple in color. The fruit of wheel milkweed is a follicle containing seeds which each having a tuft of silky hairs up to an inch long.

8. Redring Milkweed (Asclepias variagata)

Asclepias variagata commonly referred to as Redring milkweed grows between 3 to 6 feet tall. This perennial plant thrives in dry to moist, loamy to rocky open woodlands and edges of woodlands as well as sunny glades. Stems, petioles and main leaf veins are reddish in spring but become greener during the growing season. Leaves have a broadly rounded to gently tapered base and leaf blades are mostly flat, facing sunlight. It produces small white flowers with purplish centers that are crowded into round, terminal clusters. It flowers in early summer.

9. Green comet milkweed (Asclepias Viridiflora)

Asclepias viridiflora commonly referred to as Green-flower milk weed or comet milkweed grows up to 5 feet tall. The stems of this plant are mostly solitary or in pairs and bears opposite leaves up to four inches long. The stem is also light green to reddish purple color with a covered in white hairs. It produces purplish-pink to greenish-white flowers that bloom from July to August with the seeds ripening from August to October.

10. Green Antelopehorn (Asclepias viridis)

Asclepias viridis also referred to as Green Antelopehorn or spider milkweed grows 30 to 40 inches tall. Its stem is usually upright clad with mostly alternate, short-stalked, pointed, ovate-lanceote, pale green leaves.  Tiny green flowers with purple hoods bloom in many-flowered axillary and terminal umbels from May to June. Each tiny flower has 5 upright pale green corolla lobes (petals) and 5 purple hoods.