Euphorbia ​polygona var. major

Euphorbia polygona var. major

Synonyms: Euphorbia horrida var. major, Euphorbia horrida var. nova, Euphorbia polygona var. major
Family: Euphorbiaceae
Common Name: African milk barrel
Origin: Euphorbia polygona originates from the Eastern Cape of Southern Africa, dominant in rocky quartzite fields.
Description: Although now considered the same species, E. polygona and E. horrida possess slight morphological differences. E. polygona is a glaucous, cylindrical, basally clumping spurge that develops a cactus-like form of upright columns. The stem is covered in numerous peduncles, from which few to many spines emerge.
E. horrida possesses irregularly clumping stems, and a less dense form, with hairy peduncles and white striped flesh. Additionally, the ribs and spines of the major variety are distinctively wavy.
In summer, E. polygona will produce dark purple cyathia, while the inflorescence of E. horrida will be greenish-yellow.

Interesting Features:
- Because E. polygona and E. horrida possess no genetic differences, the two species have been combined, with E. polygona becoming the new accepted name. However, morphological differences are present in both species, and this specimen is of E. polygona var. major.
- The milky sap secreted from wounds is considered a minor poison or toxin, causing skin irritation, and all plant parts are toxic when ingested.
- Both E. polygona and E. horrida are hosts to the parasitic plant Viscum minimum (mistletoe) in their native habitats, but are not severely impacted by the parasitism.
Uses: While popular in cultivation, the specific ethnobotanical properties of E. horrida and E. polygona var. major are unknown. However, other Euphorbiaceae species possess anti-bacterial and anti-viral properties, historically used to treat diabetes, inflammation, syphilis, smallpox, cough, constipation, and many other ailments.

Cultivation and Care:

Watering: Moderate
- Unlike most succulents, E. polygona and E. horrida do not tolerate drought well - water moderately year-round, reducing irrigation only during the coldest part of winter.
Soil: The African milk barrel should be planted in a loamy or sandy succulent soil that is well-draining. Poor soils can be supplemented with a half-strength fertilizer fed monthly, and pH does not influence growth – however, ensure that succulents are never kept in moist soil
Lighting: E. polygona and E. horrida prefer full sun, but their smaller and more rounded varieties differ in their tolerance of light. For E. polygona var. major, provide up to 6 hours of direct sun each day, and partial shade for the remainder.
Propagation: Both species of succulents are difficult to propagate, with seeds being hard to find or germinate. Additionally, E. polygona var. major cannot be propagated from this method, as succulents are either sterile or do not come true from seed. Stem cuttings are a successful method of propagation, but should be done very carefully to avoid damage by the secreted sap.
Cold Tolerance: 25°F, USDA hardiness zones 9b to 11.
Special Accommodations: E. polygona and E. horrida var. major are hardy and can tolerate occasional frost if their roots are kept dry.
- Because varieties differ in their sun tolerance, carefully monitor the growth of E. polygona var. major, to determine if more or less sun should be provided.
- Additionally, repot as needed, and always wear gloves when handling, to prevent damage by the toxic sap and numerous spines.

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