Asclepias viridis Walter
Green antelopehorn, Green milkweed
Asclepiadaceae (Milkweed Family)
Synonym(s): Asclepiodora viridis
USDA Symbol: ASVI2
Green antelopehorn is a native, perennial forb or herb with alternate, entire leaves. The leaf margins are often wavy. Flowers are white and in an umbel, mostly one per plant. Upon close inspection, some rose or purple color is evident in the center of each individual flower (gynostegium). The milky substance that is exuded when a plant part is broken is very sticky, much resembling “Elmer’s glue.” These milkweeds bloom from late spring to middle summer.
This milkweed is common in pastures from Kansas to Texas. Generally avoided by cattle and horses. It can be found along roadsides, ditches, prairies, open areas, and other areas with little vegetative competition. The flowers are distinct in that they lack horns.
From the Image Gallery
Plant CharacteristicsDuration: Perennial
Root Type: Tap
Leaf Retention: Deciduous
Leaf Arrangement: Alternate
Leaf Complexity: Simple
Leaf Shape: Lanceolate , Ovate
Leaf Venation: Pinnate
Leaf Pubescence: Puberulent
Leaf Margin: Entire
Leaf Apex: Emarginate
Leaf Base: Truncate
Breeding System: Flowers Bisexual
Size Notes: 9 ¾ – 25 ½ in (25-65 cm).
Leaf: Leaf arrangement is alternate to sub-opposite and attachment is petiolate with short petioles. Leaves ovate to lanceolate, 2-4 ¾ in (5-12 cm) long and 3/8- 2 ¼ in (1-5 ½ cm) wide. Glabrous, but occasionally has fine sparse hairs.
Flower: Usually one umbel per stem but large plants may have up to 10 stems and infloresences, 3-5 in (7 ¾ -12 ¾ cm) wide with 10 +/- flowers per umbel. Color is white to yellow-green with a purple tinge. Corolla is green or cream. Hoods are purple to white. Corolla cups upward and around the outside of the hoods. Doesn’t have horns.
Fruit: Pods usually erect, 2 ½ -5 in (6-13 cm) long and ½ – ¾ in (1-2 cm) wide. Slightly hairy.
Size Class: 1-3 ft.
Bloom InformationBloom Color: White , Yellow , Green , Purple
Bloom Time: Apr , May , Jun , Jul , Aug , Sep
Bloom Notes: Flowers details are beautiful in how they are arranged in the cluster.
DistributionUSA: AL , AR , FL , GA , IL , IN , KS , KY , LA , MO , MS , NE , OH , OK , SC , TN , TX , WV
Native Habitat: Dry areas, prairies, pastures, glades, ditches, disturbed ground, limestone soils.
Growing ConditionsWater Use: Low
Light Requirement: Sun
Soil Moisture: Moist
Cold Tolerant: yes
Heat Tolerant: yes
Conditions Comments: This is another member of the milkweed family that certain butterflies love. It can be found growing in rich or poor soils and blooms off and on over ther growing season through the end of summer. Has a spreading, open growth form. Requires little water and full sun.
BenefitWarning: All plants in the genus Asclepias are probably somewhat toxic, some fatally so, to both humans and animals. The sap of some causes skin irritation in humans. Sensitivity to a toxin varies with a person’s age, weight, physical condition, and individual susceptibility. Children are most vulnerable because of their curiosity and small size. Toxicity can vary in a plant according to season, the plant’s different parts, and its stage of growth; and plants can absorb toxic substances, such as herbicides, pesticides, and pollutants from the water, air, and soil.
Conspicuous Flowers: yes
Fragrant Flowers: yes
Nectar Source: yes
Deer Resistant: High
Value to Beneficial InsectsSpecial Value to Native Bees
Special Value to Bumble Bees
Special Value to Honey Bees
Supports Conservation Biological Control
This information was provided by the Pollinator Program at The Xerces Society for Invertebrate Conservation.
PropagationPropagation Material: Seeds
Seed Collection: June-July
Seed Treatment: Soak seed overnight in water. Cold moist stratification for 14-30 days enhances germination to greater than 60 percent.
Commercially Avail: yes
Find Seed or Plants
Order seed of this species from Native American Seed and help support the Wildflower Center.
From the National Suppliers DirectoryAccording to the inventory provided by Associate Suppliers, this plant is available at the following locations:
Wrights Nursery - Briggs, TX
From the National Organizations DirectoryAccording to the species list provided by Affiliate Organizations, this plant is on display at the following locations:
Lady Bird Johnson Wildflower Center - Austin, TX
Texas Discovery Gardens - Dallas, TX
Stengl Biological Research Station - Smithville, TX
NPSOT - Austin Chapter - Austin, TX
NPSOT - Williamson County Chapter - Georgetown, TX
Wildflower Center Seed BankLBJWC-1757 Collected 2015-08-10 in Burnet County by Lady Bird Johnson Wildflower Center
LBJWC-1806 Collected 2015-09-09 in Johnson County by Lady Bird Johnson Wildflower Center
LBJWC-1786 Collected 2015-06-26 in Hunt County by Lady Bird Johnson Wildflower Center
LBJWC-1779 Collected 2015-09-05 in Lee County by Lady Bird Johnson Wildflower Center
LBJWC-1759 Collected 2015-07-17 in Williamson County by Lady Bird Johnson Wildflower Center
LBJWC-1794 Collected 2015-10-15 in McLennan County by Lady Bird Johnson Wildflower Center
LBJWC-1710 Collected 2015-08-16 in Hays County by Lady Bird Johnson Wildflower Center
BibliographyBibref 328 - Wildflowers of Texas (2003) Ajilvsgi, Geyata.
Bibref 286 - Wildflowers of the Texas Hill Country (1989) Enquist, M.
Search More Titles in Bibliography
Web ReferenceWebref 20 - Milkweed Profiles (0) Monarch Watch
Additional resourcesUSDA: Find Asclepias viridis in USDA Plants
FNA: Find Asclepias viridis in the Flora of North America (if available)
Google: Search Google for Asclepias viridis
MetadataRecord Modified: 2015-09-14
Research By: NPC, RLU, DEW