Euphorbia mammillaris (yoo-FOR-bee-uh mam-mil-LAIR-iss)
Family: EuphorbiaceaeNon-native
Non-native
Indian corn cob is a succulent, short-stemmed, columnar, cactus-like plant in the spurge family (Euphorbiaceae) native to South Africa. It is studded with occasional spikes that resemble toothpicks . This plant prefers full sun and well-drained soil. Water once a week in the summer and up to once a month in the winter. It is best to allow the soil to dry out between waterings. With plenty of space and sunlight, Indian corn cob can reach 1 foot or more in height and sprout new branches from its base. Plant in containers with good drainage holes in potting soil appropriate for succulents and cacti. Provide plenty of bright light if indoors. A diluted fertilizer can be applied in late spring to summer. This is a drought-tolerant, fast-growing, and lives a long time once it is established. Propagation can be done with stem cuttings in spring or summer. The stems are chalky-green, thick, erect, ribbed, short, and club-like. They have thick, blunt spines that are scattered over the stems. The leaves are small, green, and short-lived. Tiny orange to pink flowers appear in the late winter to early summer. The blooms are small and appear in clusters at the tip of the stems. In NC, the plant is grown as a houseplant that can be taken outdoors during summer if desired. The Indian corn cob is toxic if ingested. Keep small children and pets out of reach of this plant. The plant contains a white sap that can irritate the skin and eyes. Protective gloves are recommended when handling this plant. Insects, Diseases, and Other Plant Problems: Monitor for mealybugs and spider mites. Powdery mildew and root rot are potential diseases. Root rot occurs with overly moist and poorly drained soils. This plant needs protection from strong winds to prevent the stems from becoming injured which can result in permanent scarring. VIDEO Created by Laura Barth for "Houseplants, Succulents, and Cacti," a plant identification course offered in partnership with Longwood Gardens. More information on Euphorbia .
Curated pairwise relationships between this plant and others in the library — who feeds
whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.
No curated interactions recorded for this species yet.
Also noted by NC State
Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell
apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.
Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Loam (Silt); Sand
Soil pH
Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage
Growth rate
Medium
Maintenance
Low
Form & Appearance
Habit / form
Erect; Spreading
Texture
Medium
Leaf color
Green
Leaf type
Simple
Leaf size
< 1 inch long
Hairs present
No
Leaf detail
The leaves are small, up to 0.25 inches long, green, and short-lived.
Flower color
Gold/Yellow
Flower form
Insignificant
Flower shape
Cup
Flower size
< 1 inch
Flower detail
It produces a cup-shaped involucre of fused bracts enclosing several greatly reduced male flowers and a single female flower at the tip of each stem in late winter to early summer.
Bloom time
Spring; Summer; Winter
Fruit detail
Obtusely lobed, up to 0.25 inch in diameter, subsessile.
Stem color
Gray/Silver; Green
Stem detail
Thick, erect, succulent gray-green stems with 7-17 ribs, scattered spikes and club-like lateral branches.
Wildlife & Ecology
Native status
Non-native
Origin
Cape Provinces, South Africa
Landscape Use
Landscape location
Container; Houseplants; Patio
Landscape theme
Drought Tolerant Garden; Rock Garden
Design feature
Border
Garden tags
#houseplant #succulent #drought tolerant #full sun tolerant #patio #problem for dogs #problem for cats #contact dermatitis #poisonous #spines #problem for children #rabbit resistant #rock garden #border planting #dry soils tolerant #low maintenance #container plant #poisonous if ingested #deer resistant
Problems & Resistance
Insect problems
Mealybugs
Problems
Contact Dermatitis; Poisonous to Humans; Problem for Cats; Problem for Children; Problem for Dogs
Resistant to
Deer; Drought; Dry Soil; Rabbits
Propagation
Stem Cutting
Poison severity
Low
Poison parts
Flowers; Sap/Juice; Seeds; Stems
Poison symptoms
The milky white latex sap found in all plant parts can cause mild to severe contact dermatitis. If contact with the eyes occurs the sap can cause temporary to permanent damage to the cornea. If eaten, blistering can occur on lips and oral mucosa. Avoid ingesting plant parts and keep plants away from pets and children.