What is Sunlight Black Cardinal?
Sunlight black cardinal is a foliage houseplant with strikingly dark leaves. It has oval-shaped leaves that emerge bright red and mature to a deep purple-black. Its proper botanical name is Solenostemon scutellarioides‘Cardinalis’. Originally from India, Southeast Asia, and Africa, sunlight black cardinal was hybridized in England around 1860 and has since become a popular houseplant.
With its intense color, sunlight black cardinal makes an eye-catching ornamental plant. It thrives on little light but prefers bright, indirect light for the most vibrant leaf color. Sunlight black cardinal requires consistently moist soil and humid conditions. During the growing season in spring and summer, fertilize the plant every few weeks. Pruning encourages fuller growth, and pinching back the stems will produce a bushier plant. Sunlight black cardinal can live for several years and reach up to 3 feet tall indoors.
Sunlight black cardinal is relatively low-maintenance but can be prone to a few problems. Watch for common pests such as aphids, spider mites, and mealybugs and treat them promptly to avoid damage. Leaf drop or spots on the leaves can indicate too much or too little light or water. Repotting a potbound sunlight black cardinal will usually revive a plant that shows slowed growth. With the proper care and conditions, sunlight black cardinal will reward you with years of its dramatic dark foliage.
Origins of Sunlight Black Cardinal
Sunlight black cardinal, scientifically known as Solenostemon scutellarioides ‘Cardinalis’, is a cultivar of the species Solenostemon scutellarioides. It belongs to the mint family Lamiaceae and is native to tropical regions of Africa, Southeast Asia, and India. Sunlight black cardinal was first discovered and developed as a houseplant in England around 1860.
The species Solenostemon scutellarioides encompasses a diverse range of cultivars bred for their colorful foliage. Sunlight black cardinal specifically was hybridized to produce leaves of an intensely dark purple-black color. Breeders selected seedlings that exhibited this novel and striking pigmentation and propagated them to develop the cultivar.
Sunlight black cardinal’s lineage traces back to the species that British botanist George Bentham named Coleus scutellarioides in 1830, now Solenostemon scutellarioides. Bentham classified Coleus as part of the mint family based on its square stems and opposite, aromatic leaves. Over decades, horticulturists bred different Coleus cultivars and introduced them to Europe, sparking interest in the exotic foliage plant.
A key event was the introduction of coleus cultivars to England from Java in the 1850s. These cultivars had leaves of yellow, red, and copper hues which had never been seen before in Europe. They drew much excitement and spurred extensive hybridization in England, resulting in new cultivars with even more vibrant colors and patterns. Sunlight black cardinal emerged from this Victorian-era hybridization and has since become a classic houseplant.
Sunlight black cardinal remains a popular cultivar to this day due to its bold, dark foliage that provides contrast in shady garden beds and indoor plantings. Like other coleus cultivars, it retains a diversity of leaf shapes, sizes, and hues within the population, giving each plant a unique look. This adaptable, colorful hybrid has secured its status as a staple in shade gardens and homes around the world.
Care and Maintenance of Sunlight Black Cardinal
Sunlight black cardinal is a relatively low-maintenance houseplant but it does require certain conditions to thrive. Here are some tips for proper care of sunlight black cardinal:
Location: Sunlight black cardinal prefers bright, indirect light such as east or west facing windows that filter the sun. Direct southern exposure during summer can sunburn the leaves. Shade will cause faded, dull foliage.
Watering: Keep the soil consistently moist but not soggy. Water when the top 1-2 inches become dry. Pour water until it flows out the drainage holes at the bottom of the pot. Empty the saucer below the pot after watering.
Humidity: Mist sunlight black cardinal with a spray bottle or place on top of pebbles with some water added to increase the humidity. Ideal levels are 50-60%. Lack of humidity can cause leaf drop and browning leaf edges.
Fertilizer: Feed sunlight black cardinal every 2-4 weeks during the growing season. Use a balanced, all-purpose fertilizer at 1/2 the recommended strength. Reduce feeding in the fall and winter when growth slows down.
Pruning: Pinch or prune sunlight black cardinal to shape it and promote bushy growth. Remove stems or branches by pinching them off at a leaf node. Prune after flowering or in the spring before new growth starts.
Pests and diseases: Common pests that attack sunlight black cardinal include aphids, spider mites, and mealybugs. Treat them with horticultural oil or insecticidal soap spray. Fungal leaf spot disease can be prevented by avoiding overhead watering and moisture fluctuation. Treat with a fungicide if needed.
Repotting: Repot sunlight black cardinal every 2-3 years in the spring before the growing season. Look for roots protruding from the drainage holes or water running right through the pot. Move up one size and use fresh, well-draining potting mix.
With the right amount of light, water, and nutrients, sunlight black cardinal will thrive as a houseplant for many years. This low-fuss yet bold foliage plant can add dramatic color to indoor spaces when given proper care and conditions to support its growth.
Propagation of Sunlight Black Cardinal
Sunlight black cardinal can be easily propagated from stem cuttings or leaf cuttings. Propagation involves taking a part of the plant and stimulating it to develop roots to produce a new, independent plant. Here are the steps for propagation of sunlight black cardinal:
Select a 3-6 inch long stem that has several leaves at its tip. Remove the bottom pair of leaves.
Dip the cut end in rooting hormone (optional). This can speed up root formation.
Plant the cutting in moist propagating medium such as perlite, vermiculite, or a mixture of peat moss and perlite. Bury 1-2 leaf nodes of the stem.
Place in a warm spot with indirect light. Cover with a plastic bag to retain humidity.
Keep the medium moist but not soggy. Roots should form in 1 to 2 months.
Once rooted, pot up the new plant and care for it like a mature sunlight black cardinal.
Select 3-4 inch long leafy stems or individual mature leaves. Remove all but the top pair of leaves.
Dip the cut end in rooting hormone (optional). Place the cutting with the stalk buried in the propagating medium.
Enclose in a plastic bag and place in a warm area with indirect light.
Roots should form at the base of each leaf in 1 to 2 months. Once rooted, plantlets can be separated and repotted.
Care for the new plantlets like mature sunlight black cardinal plants. They will grow quickly with adequate light and nutrition.
Propagating coleus from cuttings is an economical way to produce new plants with attributes similar to the parent plant. Sunlight black cardinal cuttings will root readily and grow into full-sized plants in a single growing season when provided with the proper conditions. This allows you to make multiple clones of a plant with desirable leaf color and form.
Common Problems Faced by Sunlight Black Cardinal Owners
While relatively low-maintenance, sunlight black cardinal can face certain issues that may require treatment. Here are some common problems encountered by sunlight black cardinal owners and solutions:
Leaf drop: If sunlight black cardinal drops leaves excessively, it usually indicates a stress factor such as overwatering or underwatering, extreme temperatures, or lack of light. Improve watering, move to suitable temperature/light conditions and the plant should recover.
Spots on leaves: Fungal or bacterial leaf spot disease often causes spots on sunlight black cardinal leaves. Prevent overhead watering, improve air circulation, and avoid wetting the leaves when watering. Treat with a copper based fungicide as directed. Severe infections may require pruning infected leaves.
Slow growth: Several factors can slow the growth of sunlight black cardinal including lack of nutrients, lack of light, root bound in pot, or extreme temperatures. Fertilize during the growing season, move to brighter spot, repot if necessary and place in average room temperatures. sunlight black cardinal grows most actively in warm weather.
Pests: Common pests such as aphids, spider mites, and mealybugs feed on sunlight black cardinal and secrete honeydew, causing sticky leaves. They can weaken and stunt the plant if left untreated. Control these pests with horticultural oil or insecticidal soap spray, following all directions. Repeat applications may be needed for heavy infestations.
Browning leaf edges: Brown, crispy leaf edges on sunlight black cardinal usually results from low humidity, excess fertilizer, or fluoride/chlorine toxicity. Increase humidity around the plant, flush out the excess fertilizer by overwatering, and use rain or distilled water if fluoride/chlorine are suspected. Prune off badly affected leaves and conditions should improve.
With regular monitoring and care adjustments, problems with sunlight black cardinal can usually be corrected. Watch your plant closely for early signs of stress or pest infestation and take appropriate action to return it to good health. When in doubt, a soil test or tissue analysis can be performed to check for any nutrient deficiencies before they cause long term issues with your plant.