Synadenium grantii (African Milk Bush): Care and Toxicity Warning

A reader in Arizona has a plant labeled "Synadcnium Grautii" — likely a typo for Synadenium grantii (African milk bush, milk bush, or pencil tree). It's grown from 30 cm to 1.8 m in two years and comes indoors for winter.

Identification

Synadenium grantii is a tropical succulent shrub with thick, fleshy stems and leaves. When broken, it exudes a white, latex-like sap — a hallmark of the Euphorbiaceae family.

Care Requirements

• Light: Full sun outdoors; brightest window indoors.
• Soil: Fast-draining cactus/succulent mix.
• Water: Moderate in growing season (let dry between waterings); sparse in winter.
• Fertilizer: Balanced liquid (e.g., 20-20-20) monthly spring–fall; none in winter.
• Temperature: Keep above 10 °C (50 °F). Frost kills it.

⚠️ Toxicity Warning

All parts are poisonous if ingested. The sap causes severe skin irritation, eye damage, and gastrointestinal distress. Keep away from children and pets. Wear gloves and eye protection when pruning or repotting. Wash tools and hands thoroughly after handling.

Winter Care in Arizona

Bring indoors before nights drop below 10 °C. Place in a south window. Water just enough to prevent shriveling. Expect some leaf drop — it's normal. Cut back leggy growth in spring before moving out.

This is a striking, architectural plant — just treat it with respect.