Heart-Leaf Milkweed

asclepias cordifolia

The Heart-Leaf Milkweed (Asclepias cordifolia) is a stunning perennial herb native to the slopes and woodlands of California and southern Oregon. Instantly recognizable by its striking heart-shaped, clasping leaves that wrap directly around dark purple stems, this resilient wildflower brings vibrant life to dry, rocky environments. In late spring and early summer, it produces spherical clusters of beautiful, deep-maroon to pink star-shaped flowers that emit a sweet, heavy fragrance, drawing in a wide variety of native pollinators. Beyond its visual charm, Heart-Leaf Milkweed plays a crucial role in Western ecosystems as an essential larval host plant for the monarch butterfly, providing nourishment and defense mechanisms for developing caterpillars. It has also historically held ethnobotanical value, with Native American tribes utilizing its strong stem fibers for cordage and its sap for various medicinal applications. This tough plant is a true symbol of West Coast chaparral and open forest habitats. Learn to recognize Heart-Leaf Milkweed in the wild using the Snappit field guide app.

Habitat: Found on dry, rocky slopes, chaparral, and open coniferous forests at elevations between 50 and 2,000 meters.

Appearance

This herbaceous perennial grows up to 100 centimeters tall, featuring thick, upright stems that are often a rich, purplish-green. Its most distinctive feature is its opposite, clasping, heart-shaped (cordate) leaves that lack stalks, appearing to embrace the stem directly. The leaves are bluish-green, sometimes tinged with purple. Its nodding flower clusters (umbels) bear numerous star-like blossoms, each with deep-maroon to purplish-pink hoods and reflexed petals, creating a complex and beautiful multi-layered appearance.

KingdomPlantaePhylumTracheophytaClassMagnoliopsidaOrderGentianalesFamilyApocynaceaeGenusAsclepias

Heart-Leaf Milkweed

Interesting facts

Its specific epithet 'cordifolia' translates from Latin to 'heart-leaved', directly referencing its beautifully shaped, clasping foliage.

Monarch butterfly caterpillars that eat Heart-Leaf Milkweed incorporate the plant's cardiac glycosides into their own bodies, making themselves highly toxic to birds.

The strong, fibrous bark of the stems was harvested by indigenous peoples, such as the Miwok, to spin high-quality ropes, fishing lines, and nets.

Special abilities

The plant produces a milky latex sap rich in cardenolides, which are toxic cardiac glycosides that deter most herbivores from eating its tissues.

Its broad, clasping leaves act as efficient funnels, capturing dew and sparse rainwater and directing it down the stem directly to its root system.

It possesses a deep, woody taproot system that stores water and nutrients, allowing it to survive hot, dry summers and regenerate after wildfires.

Measurements & details

Length: 30-100 cm
Lifespan: 5-20 years

Diet & Feeding

As a photoautotroph, this plant manufactures its own food through photosynthesis, utilizing sunlight, carbon dioxide, and water while absorbing key nutrients from the soil.

Primary Foods

Sunlight
Water
Carbon dioxide
Soil nitrogen

Foraging Method

Photosynthesis

Ecological connections

host plant

Monarch Butterfly

Danaus plexippus

Caterpillars of the monarch butterfly feed exclusively on milkweed foliage, storing the plant's toxins to defend themselves against predators.

mutualism

Yellow-faced Bumble Bee

Bombus vosnesenskii

Yellow-faced bumble bees frequently visit the flowers to gather nectar, serving as crucial pollinators for the species.

eaten by

Large Milkweed Bug

Oncopeltus fasciatus

This specialized insect feeds on the seeds and plant fluids, utilizing the milkweed's toxins for its own defense.

Traits

No trait badges are assigned for this object yet.

Also known as

No aliases listed yet.

Collections

Collections for this object will appear here as more themes are added.

Safety

Danger

1/5 · Very low

No special safety notes yet.

Frequently Asked Questions

How to identify Heart-Leaf Milkweed?

The easiest way to identify Heart-Leaf Milkweed is to use the Snappit nature identifier app.

How long is Heart-Leaf Milkweed?

30-100 cm

How long does Heart-Leaf Milkweed live?

5-20 years

What does Heart-Leaf Milkweed eat?

As a photoautotroph, this plant manufactures its own food through photosynthesis, utilizing sunlight, carbon dioxide, and water while absorbing key nutrients from the soil.

Where is Heart-Leaf Milkweed usually found?

Found on dry, rocky slopes, chaparral, and open coniferous forests at elevations between 50 and 2,000 meters.

How does Heart-Leaf Milkweed hunt?

Photosynthesis