Unveil the hidden truth about the coral cactus, a fascinating succulent, not a cactus at all. Whether indoors or outdoors, these popular plants offer a unique addition to your plant collection. Expert gardener Madison Moulton unravels the secrets of growing and caring for these captivating succulents.
Delve into the realm of succulents and behold the enigmatic beauty of the coral cactus.
At your local nursery, you may have marveled at this peculiar plant’s fan-shaped tops emerging from thick stems, adorned with striking spines and alluring colors.
Discover the intriguing story behind this exotic appearance and the specialized care it demands. Explore the reasons why cultivating these mesmerizing succulents can be a rewarding experience.
Coral Cactus Plant Overview
Plant Type
Succulent
Family
Euphorbiaceae
Genus
Euphorbia
Species
Euphorbia neriifolia
Native Area
Asia
Exposure
Partial to Full Sun
Height
2 feet
Watering Requirements
Low
Maintenance
Low
Soil Type
Succulent Mix
Hardiness Zone
11-12
Pests and Diseases:
Scale, Spider Mites, Mealybugs
About Coral Cactus
This is a unique and peculiar plant with unusual shapes, spines, and colors that make it look like an alien.
Resembling an extraterrestrial being rather than a typical plant, the coral cactus may deceive you on first glance. Despite its alien-like appearance, it can be found alongside other succulents at your local nursery. With its strange shapes, captivating spines, and distinctive colors, the coral cactus truly stands out.
This distinct appearance results from the fusion of two Euphorbia species. The coral cactus we recognize is a union of two plants – Euphorbia neriifolia at the base and Euphorbia lactea var. Cristata atop.
Euphorbia lactea boasts intriguing spines and is grafted onto the sturdier Euphorbia neriifolia, forming a tree-like structure comprising two entirely different plant species.
Although dubbed the coral cactus due to its resemblance to sea coral, it is also known as the candelabra plant or crested euphorbia. Despite its misleading name, this plant is not a cactus but technically categorized as a succulent, belonging to the vast Euphorbiaceae family, akin to poinsettias.
Unlike desert cacti that thrive in intense sunlight, these Euphorbia species can tolerate lower light levels. Their preference for mild temperatures and minimal sunlight requirements has made them popular indoor plants worldwide, although they can flourish even better outdoors in suitable climates.
Native Area
Numerous varieties of this succulent are cultivated for decorative purposes.
While species in the Euphorbia genus primarily hail from Africa, the two species composing the coral cactus originate from Asia, specifically the Indian subcontinent.
Several cultivars of this species are cultivated for ornamental uses. ‘Cristata’ is commonly favored, but there are other intriguing cultivars available. ‘White Ghost’ is a personal favorite, captivating me from the first glimpse and thriving in my home for several years.
Unlike desert cacti adapted to bright sunlight, these Euphorbia species are more adaptable to lower light conditions. Due to their tolerance for dimmer light and preference for moderate temperatures, they have become popular household plants globally. However, if you reside in a suitable climate, outdoor growth can further enhance the plant’s performance.
Characteristics
Indoor Light Requirements
A minimum of 4 hours of direct sun per day is recommended for your indoor coral cactus. Optimal placement would be near east-facing windows for morning sun and bright, indirect light in the afternoons. While they can tolerate full-day sun exposure, intense afternoon sunlight may lead to scorched leaves.
Outdoor Light Requirements
Outdoor coral cacti thrive best in full sun or afternoon shade, depending on your location. In milder climates with less intense summer sunlight, full-day sun exposure is suitable for these succulents.
If your region faces harsh afternoon sun, provide some shade to prevent damage, especially for lighter-colored varieties that are prone to scorching in high temperatures.
To prevent damage, gradually acclimate your succulent to new lighting conditions over one to two weeks. For instance, if they were previously under full sun at the nursery, expose them to ample direct light indoors until they adapt.
To adapt to lower light levels, if the plant is located in the indoor garden section where it receives indirect light, avoid abruptly moving it into full sun to prevent potential burning.
Water
Water when the soil is about to dry out but not completely dry.
Operating as a water-storing succulent, the coral cactus has the capability to survive short periods with its stored water reserves in the stems. However, unlike desert cacti, it is not as resilient. Prolonged dry soil exposure will cause the stems to wrinkle and shrink, leading to stress and growth issues.
Conversely, overwatering poses a significant threat to these plants. Excessive watering can result in root and base rot, eventually killing the entire plant. Root rot correction is complex once established, emphasizing the importance of preventative measures.
It is advisable to water the plant when the soil is on the verge of drying out. While it should not be completely dry for more than a few days, missing a watering session for a day or two is unlikely to cause lasting harm. Before watering, test the soil moisture by either checking with your finger or lifting the pot.
The watering frequency is influenced by the environmental conditions. Direct sunlight accelerates soil drying compared to bright indirect light. Regularly assess the soil to determine the required watering schedule.
Seasonal changes also impact water needs. Increased watering is necessary during warm spring and summer weather, while reduced frequency in fall and winter minimizes the risk of rot.
Soil
To ensure it’s happy in its new home, repot your plant with soil similar to its current texture.
Ensuring proper drainage and preventing waterlogging, succulents require a specific soil mix. Conventional potting soil is inadequate for these plants, especially when kept indoors. Additionally, garden soil is unfavorable due to poor drainage and the potential introduction of weed seeds, pests, or diseases.
Opt for specialized succulent and cacti potting mixes when planting in containers as they are designed to enhance drainage and provide the preferred gritty texture. If preferred, you can enrich potting soil with sand and perlite to create your own mix.
Soil considerations typically arise during repotting, which is infrequent. When repotting, try to replicate the existing soil texture as closely as possible to facilitate the plant’s acclimatization and minimize transplant shock.
In outdoor containers.Keeping your potted plants under the sun would demand less watering due to quicker soil drying. Still, it’s vital to maintain proper soil texture and ensure adequate drainage by using containers with ample drainage holes to prevent overwatering issues.
Temperature and Humidity
Succulents thrive in arid conditions, so humidity levels are not crucial.
Avoid exposing this plant to cold temperatures as it is intolerant to chilly weather. Hailing from warm climates where temperatures seldom fall below 60°F, they are extremely sensitive to cold and can perish quickly if subjected to prolonged cold spells.
Only individuals residing in USDA Zones 10 and above should contemplate keeping coral cactus outdoors to shield them from potential cold ramifications like frosty nights. Although these plants can handle temperatures dipping to approximately 50°F before serious harm sets in, it’s advisable to maintain temperatures consistently above 60°F throughout the year.
If you reside in colder regions, bringing your potted succulent indoors during fall and winter is an alternative. Some horticulturists opt to keep them indoors year-round as houseplants to reduce the stress of transitioning the plant in and out twice a year amidst stark environmental changes.
These succulents are not demanding in terms of humidity. They thrive in dry environments and do not rely on high humidity levels like typical houseplants. Excessive humidity can foster diseases such as powdery mildew, so be vigilant if you’re in a high-humidity location.
Fertilizing
Apply a balanced general fertilizer at half strength every 6-8 weeks during spring and summer.
Coral cactus is a slow grower that requires minimal fertilization to flourish. Nevertheless, like all container plants, its nutrient levels may deplete over time, benefiting from a light nutrient replenishment.
Opt for a balanced general fertilizer and initially apply it at half strength to prevent over-fertilization. Feed your plant this way roughly every 6-8 weeks in spring and summer. Cease fertilizing during fall and winter to provide the plant with a rest period.
Propagation
Use a clean and sharp knife for propagation via grafting.
Given that coral cactus is a crossbreed of two distinct species, it necessitates grafting to propagate rather than conventional succulent propagation methods. To expand your collection, you’ll have to graft new plants using separate Euphorbia neriifolia and Euphorbia lactea var. Cristata species.
Grafting is a complex process that demands precision. It’s advisable to purchase a new plant instead of attempting to graft one on your own to ensure successful propagation.
Grafting Challenges and Risks
Grafting a plant is a more intricate process than propagating it naturally. There are risks involved, such as the potential for disease or decay if done improperly. Additionally, an unsuccessful graft could hinder the plant’s future growth due to healing issues.
Step-by-Step Coral Cactus Grafting Guide
For seasoned gardeners seeking a challenge or a new experiment, grafting a coral cactus can be an exciting project.
Begin with healthy specimens of Euphorbia neriifolia and Euphorbia lactea var. Cristata species for higher success chances. Utilize a sanitized sharp knife to prevent bacterial transfer during cutting. Initiate the process by creating a V-shaped incision downwards into the Euphorbia neriifolia stem. Avoid straight cuts that may lead to unstable healing.
Next, carve an arrow shape of the same size at the base of the Euphorbia lactea var. Cristata crest, ensuring a snug fit when joining the two parts. Gently place the top portion onto the base plant, ensuring a seamless connection without any gaps to promote proper healing.
Secure the sections using twine or grafting tape to maintain contact between the cut surfaces. Keep the plant in a well-lit area for recovery and water as needed, allowing the soil to slightly dry out between watering sessions.
After a few weeks, the graft should heal. At this stage, remove the twine or tape to allow normal growth to continue.
Repotting Guidelines
Spring and summer are ideal for repotting. Use a succulent-specific soil mix for best results.
Given their slow growth and maintained size post-grafting, frequent repotting isn’t necessary. The plant can thrive in its current container for several years without issues.
However, periodic soil refreshing every three to four years is beneficial as the soil quality deteriorates over time. Simply replant in the same pot. Repotting can also be done for drainage improvement or aesthetic reasons.
It’s advisable to repot during the warmer months, opting for a larger pot if needed and utilizing the same soil mix to maintain consistent conditions.
Common Issues and Solutions
Various common problems may arise when caring for a coral cactus, necessitating specific remedies for prolonged plant health.
New Branch Growth at the Base
Natural growth processes can result in extra branches at the plant’s base, which can be pruned or retained based on preference.
It’s common for coral cacti to develop additional branches at the base, a natural growth occurrence. These branches can be maintained or trimmed to restore the plant’s original form.
Wrinkling Concerns
Wrinkling could indicate inadequate watering or root problems, necessitating adjustment in watering frequency or potential repotting.
Wrinkling of the plant can suggest drought stress. Despite the ‘cactus’ in its name, these plants require some watering attention. While they prefer less water compared to typical houseplants, they still need adequate moisture to thrive.
Soil Moisture
Long periods of dry soil are not favored by Coral Cactuses. If deprived of moisture, their stems can shrivel and develop wrinkles until the plant receives adequate watering.
Shriveling is not exclusively caused by underwatering; it can also be a sign of overwatering. However, in cases of overwatering, mushy stems and yellowing are usually present. If you suspect root rot, refrain from watering for a while and consider repotting the plant as necessary.
Yellowing
Yellowing could result from overwatering due to poor drainage.
Yellowing in a succulent might indicate overwatering, commonly due to inadequate drainage. It could also occur from frequent watering while the topsoil is still moist. If yellowing is accompanied by soft stems, urgent repotting and root trimming might be necessary to salvage the plant.
Pests
Common pests like spider mites, scale, and mealybugs can affect this houseplant, treatable with rubbing alcohol.
Coral Cactuses are prone to various pest issues including spider mites, scales, and mealybugs. Battling mealybug infestations in Euphorbias is a common challenge. While some pests can be manually removed, severe infestations might require spot treatment with rubbing alcohol for effective eradication.
There are also potential diseases to be cautious of, such as powdery mildew and root rot, although these occurrences are less frequent. Proper care and prompt resolution of any issues can prevent their escalation.
Coral Cactus Flowering?
While Coral Cactus can produce flowers, this occurrence is quite rare, particularly when cultivated indoors. Their allure lies more in their captivating forms than their often overlooked flowers.
Final Thoughts
If you’re seeking a distinctive plant for indoor or outdoor cultivation, Coral Cactus is an excellent choice. These plants are certain to spark conversations and require minimal upkeep to thrive.
Indoor Coral Cactus thrive with a minimum of 4 hours of direct sunlight daily, making east-facing windows the optimal choice. While they can tolerate full sun exposure, intense afternoon sunlight may lead to leaf scorching.
For outdoor Coral Cactus, consider planting them in full sun or providing afternoon shade, depending on your location. In regions with moderate climates, these succulents can handle a full day of sun without issues.
In areas where the afternoon sun is harsh, protective measures are advised, especially for lighter-colored varieties susceptible to heat damage.
Handling Coral Cactuses requires caution as their sap can irritate the skin, with more severe effects if it comes into contact with eyes or if ingested. Wearing gloves is recommended to prevent potential issues, especially for individuals with sensitive skin, and keep them away from pets and children.
Coral Cactus, a blend of Euphorbia neriifolia and Euphorbia lactea var. Cristata, forms a striking combo where Euphorbia lactea is grafted onto the more structural Euphorbia neriifolia, resulting in a unique tree-like structure comprising two distinct plants.
Although Coral Cactus can grow up to 2 feet or slightly taller, they typically stay smaller, reaching around a foot in height due to their slow growth rate. These plants seldom outgrow their original size or pots.
Unlike other succulents, Coral Cactus cannot be propagated conventionally. To propagate new plants, one must graft new ones from separate Euphorbia neriifolia and Euphorbia lactea var. Cristata specimens.
While rare, Coral Cactus can indeed produce flowers, especially in outdoor settings. Even though their blooms are not the main attraction, they add a touch of beauty to these captivating plants.
James is an environmental gardener and passionate writer who holds a master's degree in agriculture. He graduated from Harvard University with a degree in environmental horticulture and has a particular interest in soil composition. Currently, James works as a researcher in plant research, where he continues to explore and advance knowledge in his field. His combined expertise in environmental gardening and soil science helps him contribute valuable insights to both academic and practical gardening communities.
James is an environmental gardener and passionate writer who holds a master's degree in agriculture. He graduated from Harvard University with a degree in environmental horticulture and has a particular interest in soil composition. Currently, James works as a researcher in plant research, where he continues to explore and advance knowledge in his field. His combined expertise in environmental gardening and soil science helps him contribute valuable insights to both academic and practical gardening communities.
