Crown of Thorns, a plant that blooms all year

Growing

If growing this plant outdoors, it will grow best in a container with drainage holes and well-draining soil. Crown of Thorns prefers a location with partial to full sun. Water the plant when the soil feels dry one inch below the surface. Crown of Thorns thrives with a houseplant fertilizer applied monthly. A word of caution that overwatering can cause the roots to rot, which can quickly kill the entire plant. Be sure to bring the plant inside before the temperature drops to 40 degrees Fahrenheit if your desire is to grow it year-round.

For “snowbirds” who travel south for the winter, gardeners in USDA Hardiness Zones 9, 10, and 11 can grow this plant as a perennial outdoors as a small shrub. Once established, it has good drought and heat tolerance and tolerates salt spray. It will need protection if temperatures drop to 35 degrees.

Indoors

To keep the Crown of Thorns thriving indoors, keep the temperature between 65-75 degrees Fahrenheit. It prefers partial to full sun and will reliably bloom if it has 3-4 hours of sunlight daily. Crown of Thorns is classified as a succulent, so be careful to avoid overwatering, which can result in spongy stems, leaf loss, and failure to bloom. Fertilize indoors in the spring, summer, and fall. Crown of Thorns can handle the lack of humidity prevalent in most homes during the winter. Repot only when the plant outgrows its container and replant using a rich, well drained planting medium.

Propagation

Crown of Thorns can be propagated from tip cuttings by taking the tip section of a branch from the healthy, mature plant. To ensure a high success rate, choose a stem cutting that is 2 to 4 inches long and with new leaf buds or fresh leaves at the tip. Make sure that the stem cutting is healthy and shows no signs of disease. Scheduling propagation in spring or summer will ensure the best results because the cuttings need bright light warmth. Take care when handling the plant because both the spine and the milky sap can cause skin irritation. To limit the amount of sap you come in contact with, wear gloves and dip each cutting into warm water, letting it sit in it for several minutes. Dab the end of the root cutting in rooting hormone, then place it in a paper towel in a dry place to allow it to dry and callus over for a few days before planting. Place the newly potted Crown of Thorns in a dry, warm place, and provide plenty of indirect sunlight while the cutting is still in its root phase. As with most houseplants, keep it away from pets and small children.

Diseases, pests

There are no known serious pests or diseases that are attracted to Crown of Thorns. Mealybugs can be an issue, but they can be prevented by keeping the plant well-trimmed and removing any dead leaves from the surface of the potting mix. Mealy bugs can be removed with cotton swabs soaked in alcohol. Botrytis fungal disease can also be a nuisance. This is exhibited as large, irregularly outlined brown spots on the leaves. An insecticidal soap can assist with alleviating botrytis fungal disease. Removal of dead leaves promptly and providing good air circulation are good preventative measures.

Crown of Thorns is resilient and easy to grow as long as it is not overwatered. (Remember that it is a succulent.) Whether you are looking for an exquisite houseplant or unique outdoor beauty in a container for your patio garden, you can’t go wrong with Crown of Thorns.

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