This slow-growing plant can reach 3 to 6 feet tall outdoors or 2 feet as a houseplant.
Crown of thorns grows best outdoors as a perennial in warm zones 9 through 11.
Outdoors, place it in afull-sunlocation.
The Spruce / Gyscha Rendy
Place it in a partial sun spot if it’s an intensely dry location.
Indoors, the plant will do well in a west or south-facing spot during winter.
Soil
If growing outdoors, plant in well-draining soil.
The Spruce / Gyscha Rendy
Crown of thorns is a very adaptable houseplant.
It needs a well-drainingcactus potting mix.
The root ball should be snug in a container to discourage the retention of water in the container.
The Spruce / Gyscha Rendy
If there is excess soil, it will retain water and could cause the roots to rot.
Water
Since it is a succulent, crown of thorns is very forgiving about water.
Water when the soil feels dry about 1 inch below the surface.
The Spruce / Gyscha Rendy
Water thoroughly and allow any excess to drain off.
Crown of thorns will gosemi-dormantin the winter and need less frequent watering and no food.
Temperature and Humidity
Crown of thorns likes the same room temperature that people enjoy.
The Spruce / Gyscha Rendy
Temperature-wise, a comfortable 65F to 75F is suitable.
At least half a day of sunlight is a major requirement for crown of thorns.
It also doesn’t mind the lack of humidity prevalent in most homes during the winter.
The Spruce / Gyscha Rendy
Fertilizer
From spring through fall, feed your crown of thorns with a balanced houseplant fertilizer.
Local nurseries generally only carry a few varieties.
To stop sap from flowing, spray water directly on it.
The crown of thorns may become leggy if it is not pruned to encourage leafy or branching growth.
If growing it outdoors, give the plant plenty of room.
It can grow up to 6 feet tall and about 2 feet wide.
You will also want to prune crown of thorns to keep a compact shape if it’s a houseplant.
Avoid lopping off healthy buds.
Pruning Tip
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The best time to propagate cuttings is in the spring when growth begins, but summer is also suitable.
The container should not be over an inch or two larger than the root ball.
Only repot it when it seems to be outgrowing its container.
Use cactus potting mix only.
Water thoroughly after you have placed the plant in its new home.
Overwintering
Container-grown crown of thorns can spend the summer outdoors wherever you need color or interest.
Bring it inside before nighttime temperatures dip below 50F.
Allowing the soil to dry before watering again will help avoid these problems.
How Long Does Crown of Thorns Bloom?
Crown of thorns blooms year-round.
What Do Crown of Thorns Flowers Look and Smell Like?
They do not have a fragrance.
However, the plants will appreciate mid-day shade in overly dry climates to encourage better blooms.
Yellowing Leaves
Crown of thorn leaves should be bright green.
If theleaves are yellowingand beginning to fade, it could mean the plant is underwatered.
Poor soil quality or the wrong mix punch in could also turn leaves yellow.
Dropping Leaves
Some cyclical leaf drop is expected, especially before winter when the plant rests.
When the source of the stress is eliminated, the leaves will begin to grow back.
Poor flowering may also be the result of overfertilizing.
Too much fertilizer will produce more foliage than flowers.
The plant will grow best indoors in a west or south-facing window.
When handling this plant, protect yourself from the sap and thorns with heavy gardening gloves.
Prune crown of thorns to prevent legginess and healthy growth, but avoid lopping off healthy buds.
Crown of thorns is a succulent but not a cactus.
It is often confused with a cactus because it is a spiny shrub.
Crown of Thorns, Euphorbia milii.
Crown of thorns.Pet Poison Helpline.
Euphorbia milii.Henry Shaw Cactus and Succulent Society.
