How to Grow and Care for Crown of Thorns (Euphorbia milii) (2024)

Crown of Thorns, scientifically known as Euphorbia milii, is a remarkable and delightful plant that can be an excellent addition to any garden or indoor space. Its unique appearance, vibrant colors, and low maintenance requirements make it a favorite among garden enthusiasts.

Crown of thorns is a lovely succulent that can bloom almost all year, even indoors. Thorns can be found among the thick, bright green leaves that grow along the new stem growth. The true flowers are small and green, with showy bracts in red, orange, pink, yellow, or white surrounding them.

It’s popular as a houseplant and is grown as a garden shrub in warm climates. Although flowering occurs all year, it’s most abundant in the Northern Hemisphere during the winter.

The common name refers to the thorny crown that Jesus Christ was forced to wear during his crucifixion, with the red bracts of the flowers representing his blood.

This is a tough perennial plant with thick gray thorns and oval leaves that fall off as the plant gets older. The sprawling, branching, vinelike stems can grow to be more than six feet (two meters) long, though potted houseplants are much smaller.

The two showy light red bracts (leaf-like structures attached just below flowers) surround the small, inconspicuous flowers that are borne in paired clusters and are borne in the center of the plant.

Botanical Name: Euphorbia milii

Common Name: Crown of thorns, crown-of-thorns, Christ plant, Christ thorn

Family: Euphorbiaceae

Plant Type: Succulent

Hardiness Zones: 9 – 11 (USDA)

Sun Exposure: Full to partial sun

Soil Type: Well-drained

Soil pH: Neutral to acidic

Mature Size: 3-6 ft. tall outdoors, 2 ft. tall indoors

Bloom Time: Spring, summer, fall, winter

Flower Color: Red, orange, pink, yellow, or white

Native Area: Africa

Crown of Thorns Care

The Crown of Thorns (Euphorbia milii) is a stunning succulent plant that is native to Madagascar. It is known for its thick, thorny stems and vibrant, long-lasting flowers.

Its historical presence in the Middle East led some to believe that the plant’s stems had been used in Christ’s crown of thorns, hence the common name. The plant is loose in form, spiny, and irregularly shaped, with thick, black spines.

Taking care of this plant requires attention to its lighting, soil, water, temperature and humidity, and fertilizer needs.

Light

When it comes to lighting, Crown of Thorns thrives in bright, indirect light. Place it near a sunny window where it can receive sufficient sunlight without being exposed to direct rays, especially during the scorching summer months. However, do ensure that you provide some shade during the hottest part of the day to prevent leaf burn.

In its natural habitat, the Crown of Thorns receives intense sunlight, so replicating these conditions as closely as possible will ensure optimal growth. The bright light encourages the plant to produce more flowers, adding to its beauty and charm.

If you’re growing this plant indoors, you can use artificial grow lights or fluorescent lamps to supplement natural lighting. Aim for around 12-14 hours of light per day to promote healthy growth. Remember to adjust the distance between the light source and the plant to prevent burning or scorching the leaves.

Soil

Crown of Thorns prefers well-draining soil that mimics its natural habitat. A mix of sandy soil and good quality potting mix works best for this plant. The sandy soil provides excellent drainage, preventing water from pooling around the roots.

When selecting a potting mix, look for one that is specifically formulated for succulents and cacti. These mixes usually contain a combination of materials like peat moss, perlite, and sand, which ensure proper aeration and moisture retention.

You may also consider adding some perlite or coarse sand to the soil mix to improve aeration and drainage. This will help maintain an optimal soil moisture level, preventing the roots from suffocating. Avoid using heavy clay-based soils, as they tend to retain too much moisture, leading to root rot.

Water

Watering Crown of Thorns requires a delicate balance. While it is drought-tolerant and can go without water for extended periods, it is essential to provide adequate moisture without overwatering.

Allow the top inch of soil to dry out before watering. Insert your finger into the soil to gauge the moisture level – if it feels dry, it’s time to water. Remember that it’s better to underwater than to overwater this plant, as excessive moisture can lead to root rot.

During the active growing season, typically spring and summer, you can increase the frequency of watering. However, always ensure that the soil has dried out between waterings to prevent the plant from sitting in soggy soil.

In contrast, during the dormant period, reduce watering to keep the soil barely moist. This period usually occurs in late fall and winter when the plant slows down its growth. It’s important to adjust your watering schedule accordingly to prevent the plant from becoming waterlogged.

Temperature and Humidity

Crown of Thorns is a warm-climate plant that thrives in temperatures between 65°F and 85°F (18°C and 29°C). It is highly sensitive to cold temperatures and cannot tolerate frost. Therefore, it’s crucial to protect your plant from extreme cold by moving it indoors or providing suitable insulation.

In its native habitat, the Crown of Thorns experiences warm temperatures year-round, so it appreciates a consistent and warm environment. Avoid placing it near drafty windows or in areas with fluctuating temperatures, as this can stress the plant.

In terms of humidity, this plant can adapt well to average household humidity levels. However, if you live in an extremely dry climate, consider using a humidifier or placing a tray of water near the plant to increase moisture in the vicinity. This will help create a more favorable microclimate for the plant.

Fertilizer

Feeding your Crown of Thorns is essential for robust growth and blooming. During the active growing season, use a balanced, water-soluble fertilizer with an N-P-K ratio of 10-10-10 or 20-20-20 once every two weeks. Dilute the fertilizer as per the manufacturer’s instructions and apply it to damp soil to avoid burning the roots.

The Crown of Thorns is a heavy feeder, meaning it requires regular nutrient supplementation to support its growth and flowering. The balanced fertilizer provides essential macronutrients like nitrogen, phosphorus, and potassium, as well as micronutrients necessary for overall plant health.

Avoid fertilizing during the dormant period to allow the plant to rest. Resume feeding when new growth emerges in the spring, signaling the start of the active growing season.

Types of Crown of Thorns

When it comes to the Crown of Thorns plant, there is a wide array of exciting varieties and hybrids to explore. These plants are known for their stunning and vibrant colors, making them a popular choice among gardening enthusiasts.

‘Splendens’: One of the most striking varieties of Crown of Thorns is the vibrant red variety. With its intense and eye-catching red flowers, it adds a bold and dramatic touch to any garden or indoor space.

‘Maxi Pink Cadillac’: If you prefer a softer and more delicate touch, the pink variety of Crown of Thorns might be the perfect choice for you. Its gentle pink flowers exude a sense of elegance and grace, creating a soothing atmosphere wherever it is planted.

‘Maxi Zephyr’: For those who seek a burst of sunshine in their garden, the apricot colored variety of Crown of Thorns is a must-have. Its bright and cheerful apricot colored bell-shaped flowers bring a sense of warmth and happiness to any space.

How to Propagate Crown of Thorns

Propagation of Crown of Thorns, also known as Euphorbia milii, is a rewarding and relatively simple process. This popular succulent can be propagated through stem cuttings or seeds, with stem cuttings being the most common and effective method.

When propagating through stem cuttings, it is important to select a healthy stem from the parent plant. Look for a stem that is free from disease or damage, with vibrant green coloration. Using a clean and sharp pair of pruning shears, make a clean cut just below a leaf node. This will provide the cutting with a good base for root development.

Before proceeding with the next step, it is advisable to remove any lower leaves from the stem cutting. These leaves can potentially rot when placed in the propagation medium, leading to issues with the overall success of the propagation process.

If desired, you can dip the cut end of the stem into rooting hormone. Rooting hormone contains growth-promoting substances that can help stimulate root development and increase the chances of successful propagation. While it is not necessary, many gardeners find that using rooting hormone can expedite the rooting process.

Now it’s time to prepare the propagation medium. Crown of Thorns prefers a well-draining medium to prevent issues with root rot. A mixture of perlite and peat moss is a popular choice among gardeners. This combination provides good aeration and moisture retention, allowing the cutting to establish roots effectively.

Once the propagation medium is prepared, carefully plant the stem cutting into the medium. Ensure that at least one or two leaf nodes are buried in the medium. These leaf nodes contain the potential for new growth and root development.

After planting, lightly water the cutting. It is important to water the cutting sparingly to avoid overwatering, which can lead to rotting. The propagation container can then be covered with a plastic bag or a propagating dome to create a humid environment. This humidity helps to prevent excessive moisture loss from the cutting and encourages root growth.

Place the container in a warm and bright location, but avoid direct sunlight. Crown of Thorns thrives in bright indirect light, so placing the container near a window with filtered light is ideal. Maintain the humidity by occasionally misting the cutting and monitoring the moisture levels in the propagation medium.

Over time, you will begin to see signs of successful propagation. New growth and roots will emerge from the stem cutting, indicating that it has successfully established itself. At this stage, you can gradually acclimate the new plant to normal growing conditions by removing the plastic bag or propagating dome.

Remember to be patient during the propagation process, as it can take several weeks or even months for the cutting to fully root and establish itself. With proper care and attention, you can successfully propagate Crown of Thorns and enjoy the beauty of this unique succulent in your own garden or indoor space.

Potting and Repotting Crown of Thorns

When it comes to potting and repotting Crown of Thorns, it is important to provide the plant with the right conditions for optimal growth. While this slow-growing plant does not require frequent repotting, refreshing the soil and providing adequate space every two to three years can greatly benefit its overall health and vigor.

When selecting a new pot for your Crown of Thorns, it is recommended to choose one that is one size larger than its current container. This will allow the plant’s roots to have ample room to spread and grow. Additionally, ensure that the pot has proper drainage holes to prevent waterlogging, which can lead to root rot.

The process of repotting Crown of Thorns begins by gently removing the plant from its old container. Take care not to damage the delicate roots while doing so. Once the plant is free, carefully loosen any compacted soil around the root ball to encourage healthy root growth.

Next, prepare the new pot by filling it with a well-draining potting mix. Crown of Thorns prefers a soil mix that is sandy and fast-draining, mimicking its natural habitat. You can create a suitable mix by combining equal parts of cactus potting soil, perlite, and coarse sand.

Position the Crown of Thorns in the new pot, ensuring that it is at the same depth as it was in its previous container. Gently fill the remaining space around the roots with the potting mix, pressing it down lightly to secure the plant in place.

After repotting, it is essential to water the Crown of Thorns lightly to settle the soil. Avoid overwatering, as this can lead to root rot. Allow the plant to adjust to its new home by avoiding fertilization for a few weeks. This period of adjustment will give the plant time to recover from any root disturbance and establish itself in its new pot.

With its striking appearance and minimal care requirements, Crown of Thorns is a popular choice among succulent enthusiasts. By following the proper potting and repotting techniques, you can ensure that your Crown of Thorns thrives and continues to bring beauty to any indoor or outdoor space.

Common Pests and Plant Diseases for Crown of Thorns

Crown of Thorns is generally a hardy plant and is not prone to many pests or diseases. However, it’s essential to keep an eye out for common problems such as spider mites, mealybugs, and scale insects. Regularly check the undersides of leaves and stems for any signs of infestation.

If you detect any pests, promptly isolate the affected plant to prevent the infestation from spreading. You can use organic pest control methods like insecticidal soap or neem oil to combat these pests. Follow the instructions on the product label for safe and effective use.

Spider mites are tiny arachnids that can cause damage to the Crown of Thorns plant by sucking the sap from its leaves. They are most commonly found in dry and dusty conditions, so it’s crucial to maintain proper humidity levels and regularly clean the leaves to prevent infestation.

Mealybugs are small, soft-bodied insects that often appear as white, cotton-like clusters on the plant. They feed on the sap of the Crown of Thorns, causing wilting and yellowing of leaves. To control mealybugs, you can use a cotton swab dipped in rubbing alcohol to remove them manually or apply insecticidal soap.

Scale insects are another common pest that can affect the Crown of Thorns. They appear as small, brown or black bumps on the stems and leaves. These pests also feed on plant sap, leading to stunted growth and yellowing of foliage. To eliminate scale insects, you can use a soft brush dipped in soapy water to scrub them off or use commercial insecticides specifically designed for scale insects.

Additionally, overwatering or poor drainage can lead to root rot. Ensure that the soil is well-draining and adjust your watering schedule accordingly to avoid excessive moisture accumulation. It’s best to allow the top inch of soil to dry out between waterings to prevent the roots from sitting in water for too long.

Root rot is a fungal disease that affects the roots of the plant, causing them to become mushy and discolored. To prevent root rot, it’s important to use a well-draining potting mix and avoid overwatering. If you notice any signs of root rot, such as a foul smell or blackened roots, you may need to repot the plant and trim away the affected roots.

With proper care and attention, Crown of Thorns can reward you with stunning, long-lasting blooms and add a touch of beauty to your indoor or outdoor spaces. So why wait? Start growing and caring for your Crown of Thorns today!

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