Yellow Crown of Thorns

Water the plant thoroughly and allow the top 2-3 inches of soil to dry before you water again. During the winter, you can reduce the watering and mist the plant with a spray bottle, mimicking the humid, subtropical climate where it would naturally be found. Over-watering can result in yellowing leaves and root rot.

Yellow Crown of Thorns does best in bright, indirect sunlight, at least one hour of direct sunlight per day. In bright light, the foliage takes on a pinkish hue and it will produce a few more flowers. Keep the plant away from hot or cold drafts, and make sure it receives at least 6 hours of sunlight in the summer months. Don’t put it in a place with full sunlight exposure that can cause the leaves to burn.

Euphorbia milii prefers normal household temperatures around 65-85°F and does not tolerate temperatures below 50°F. You should keep the temperature fairly constant, avoiding sharp variations.

Average to moderate indoor humidity levels of 40-50% are acceptable for a Yellow Crown of Thorns. Misting your plant regularly, or placing the pot on top of a drip tray filled with rocks and water, is enough to increase the humidity levels and create a microclimate for your plant.

Euphorbia milii prefers a well-draining soil such as a cactus and succulent mix with fine gravel. This will help the plant to dry quickly after watering and avoid root rot.

Feed Euphorbia milii with a liquid fertilizer during its active growing season from late spring to early fall. If you’ve just repotted, make sure to wait at least a month before feeding. During the winter, avoid fertilizing as the plant is not actively growing at this time.

Yellow Crown of Thorns is generally very resistant to pests, but it can suffer from spider mites, mealy bugs and aphids, particularly when kept in a warm, dry atmosphere. To prevent these infestations, brush the plant regularly with a soapy, lukewarm solution or apply a neem oil solution to the foliage and stems of the plant. If your plant gets into an infested state, you can use cotton wool dipped in rubbing alcohol to remove them.

Yellow Crown of Thorns typically needs repotting every 1-2 years in the spring, using a well-draining potting soil with slow-release fertilizer. Repot in a pot one size larger than the existing pot to allow for further growth.

Pruning Euphorbia milii isn’t necessary, but if you want to keep a neat shape, you can lightly prune the tip of its branches, making sure not to touch the thorns. You can also prune it to control its growth and size. Make sure to prune any dead or damaged branches and stems.

Using mulch around the base of the plant will add organic matter to the soil and help with water retention.

Euphorbia milii can be easily propagated from stem cuttings. Simply cut the stem towards the base, strip the bottom leaves and place the cutting in a well-draining potting medium. Keep the cutting in water until new roots form, water every 2 or 3 days and place it in a bright, warm area. The cutting will take several months to grow and establish.

Euphorbia milii can benefit from a support to keep its shrub shape. You can use a stake or bent plant ties to give it physical support.

Euphorbia milii goes through an annual resting period in the fall and winter months, when it prefers very little water and fertilizer. During this period, the foliage will dry out and the growth rate will slow down.

Euphorbia milii is toxic to cats and dogs, and can cause significant irritation if ingested.