Corn Cob Plant Euphorbia mammillaris
Other Common Name(s):
Previously known as:
- Euphorbia fimbriata
- Phonetic Spelling
- yoo-FOR-bee-uh mam-mil-LAIR-iss
- This plant has low severity poison characteristics.
- See below
- Description
-
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 Indian corn cob grows up to 10 to 14 inches tall. 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. Yellow 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.
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.
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.
VIDEO Created by Laura Barth for "Houseplants, Succulents, and Cacti," a plant identification course offered in partnership with Longwood Gardens.
- Profile Video:
- See this plant in the following landscape:
- Cultivars / Varieties:
-
- 'Monstrose'
bright green with red spines that fade with age - 'Variegata'
creamy green color with tiny leaves and spikes
- 'Monstrose'
- 'Monstrose', 'Variegata'
- Tags:
- Cultivars / Varieties:
-
- 'Monstrose'
bright green with red spines that fade with age - 'Variegata'
creamy green color with tiny leaves and spikes
- 'Monstrose'
- 'Monstrose', 'Variegata'
- Tags:
-
-
Attributes:
- Genus:
- Euphorbia
- Species:
- mammillaris
- Family:
- Euphorbiaceae
- Life Cycle:
- Perennial
- Recommended Propagation Strategy:
- Stem Cutting
- Country Or Region Of Origin:
- Cape Provinces, South Africa
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-
Whole Plant Traits:
- Plant Type:
- Houseplant
- Succulent
- Habit/Form:
- Erect
- Spreading
- Growth Rate:
- Medium
- Maintenance:
- Low
- Texture:
- Medium
- Appendage:
- Spines
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-
Cultural Conditions:
- Light:
- 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
- USDA Plant Hardiness Zone:
- 9a, 9b, 10a, 10b, 11a, 11b
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-
Fruit:
- Fruit Description:
- Obtusely lobed, up to 0.25 inch in diameter, subsessile.
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-
Flowers:
- Flower Color:
- Gold/Yellow
- Flower Inflorescence:
- Insignificant
- Flower Bloom Time:
- Spring
- Summer
- Winter
- Flower Shape:
- Cup
- Flower Petals:
- Bracts
- Flower Size:
- < 1 inch
- Flower Description:
- 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.
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-
Leaves:
- Leaf Color:
- Green
- Leaf Type:
- Simple
- Hairs Present:
- No
- Leaf Length:
- < 1 inch
- Leaf Description:
- The leaves are small, up to 0.25 inches long, green, and short-lived.
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-
Stem:
- Stem Color:
- Gray/Silver
- Green
- Stem Is Aromatic:
- No
- Stem Surface:
- Corky Ridges
- Stem Description:
- Thick, erect, succulent gray-green stems with 7-17 ribs, scattered spikes and club-like lateral branches.
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-
Landscape:
- Landscape Location:
- Container
- Houseplants
- Patio
- Landscape Theme:
- Drought Tolerant Garden
- Rock Garden
- Design Feature:
- Border
- Resistance To Challenges:
- Deer
- Drought
- Dry Soil
- Rabbits
- Problems:
- Contact Dermatitis
- Poisonous to Humans
- Problem for Cats
- Problem for Children
- Problem for Dogs
-
-
Poisonous to Humans:
- Poison Severity:
- Low
- 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.
- Poison Toxic Principle:
- Diterpene esters in milky latex
- Causes Contact Dermatitis:
- Yes
- Poison Part:
- Flowers
- Sap/Juice
- Seeds
- Stems
