What it is: This listing is a plant sold as Monadenium Guenteri, now usually listed as Euphorbia guentheri.

Light: Give it a bright window and a very well-drained mix such as our succulent and cacti soil. In our dark northern Alberta winters, a grow bulb in a lamp helps.

Watering & care: Allow the mix to dry between waterings, and water less often in winter. Overwatering can cause rot.

Humidity: Average household humidity is fine; University of Wisconsin Extension notes crown of thorns does well in the dry air of heated northern homes, and the same usually suits other potted euphorbias.

Temperature: Keep it in typical indoor temperatures and off cold windows. These are not frost-hardy houseplants; NC State Extension treats several of these species as outdoor plants only in very warm climates, and African milk tree should be brought in before temperatures drop below about 7 °C (45 °F) (NC State Extension).

Winter indoors: In winter, water less often and keep it off cold glass, in your brightest window or under a grow light.

Expected indoor size: We don't have a reliable published indoor mature size for this selection from a university extension or similar source. How large yours gets depends on light, pot size and care.

Feeding: Feed sparingly with our Cactus Fertilizer during the growing season, and ease off in winter. The Royal Horticultural Society suggests a dilute low-nitrogen feed monthly in the growing season for potted Euphorbia obesa; other succulent euphorbias likewise do better with light feeding than with a heavy dose.

Pets & pests: We don't have a reliable published toxicity listing for this exact selection from ASPCA or a university extension, so we aren't making a species-specific pet-safety or toxicity claim here. Closely related euphorbias have an irritant, toxic milky sap (NC State Extension), so it's safest to wear gloves when handling this one and keep it out of reach of pets and children. Watch for mealybugs and other common succulent pests.

About your plant: Every plant is a little different. Size, fullness, leaf count and variegation or colouring vary from plant to plant and change with age and light, so we can't promise a particular plant size, branching, markings or flower colour. The size option (4") refers to the pot diameter. It does not guarantee an exact plant size or branching. Photos show typical plants from our greenhouse, not the specific plant you will receive. The shared gallery image shows other Euphorbia as inspiration.