How to Plant, Grow, and Care for ‘Black Magic’ Colocasia

Also known as elephant ear plants, members of the Colocasia genus are known for their large leaves that appear atop long petioles. Their impressive size makes them excellent additions to ornamental gardens, and their low-maintenance requirements mean you don’t have to spend lots of time caring for them.

Many varieties of elephant ear plants have green foliage, but ‘Black Magic’ is a cultivar known for its deep purple leaves. The plants grow between three and six feet tall, making them an excellent backdrop for smaller plants or a perfect filler when mixed with other elephant ear cultivars. You can even grow them indoors in pots if you live in a colder climate.

Although these plants are easy to grow, they still require particular care. I’ll share how to select the proper environment, overwinter the plants successfully, and care for them so they thrive.

What Is ‘Black Magic’ Colocasia?

‘Black Magic’ is a specific cultivar of Colocasia esculenta. This species is also known as taro, and is often grown for its edible, starchy corms.

It’s a tropical plant that thrives in areas that remain above freezing year-round. In these areas, the plants can grow up to six feet tall with large leaves that resemble elephant ears.

‘Black Magic’ is an ornamental variety bred for its deep purple leaves. It makes a great addition to summer landscapes, and it can also be grown indoors in containers.

Characteristics

‘Black Magic’ colocasia is a tender perennial with large leaves. It’s hardy down to zone 8, but the foliage will die back when temperatures dip below freezing.

The shield-shaped leaves have long stems known as petioles and resemble elephant ears. Each leaf emerges from the base of the plant, and leaves of various ages and heights combine to create a round, dense plant.

‘Black Magic’ leaves are deep purple, and they almost appear black from a distance. The leaves lie close to parallel to the soil line with the tips pointing towards the ground. Unlike members of the closely related Alocasia genus, ‘Black Magic’ features leaf tips that droop slightly towards the ground.

These plants produce flowers, but they aren’t attention-grabbing. Like all members of the Araceae family, the flowers consist of a single leaf called a spathe surrounding a flower spike known as a spadix. ‘Black Magic’ plants produce these flowers below the leaves, so they’re rarely seen.

Native Area

Colocasia esculenta is native to parts of Southeast Asia and India, where it thrives in hot, damp climates. ‘Black Magic’ was created by plant breeders, so it’s not native to a particular area. However, you may find it growing wild in places where it escaped cultivation.

Planting

You can grow ‘Black Magic’ colocasia from the bulbs, which are technically corms, or from potted, presprouted corms. Either method works well, but it’s not always possible to find the plants nearby. If you end up purchasing ‘Black Magic’ online, buying the corms is an easier option.

You can plant the corms or small plants in the ground or in a container. If you opt for a pot, select a container that’s at least 18 inches deep and 18 inches wide. Ensure the planter has drainage holes and fill it with a rich and well-draining potting mix.

Planting Corms

If you’re starting with a corm, wait until the soil has warmed and the danger of frost is gone. I recommend waiting until nighttime temperatures are consistently above 50°F (10°C) if you’re planting outdoors. If you’re growing ‘Black Magic’ indoors in a container, the spring is an ideal time to plant the corm.

Examine each corm and look for the bumpy or pointed side and the flat side. The narrow or bumpy end should be pointed up, and the smooth side should be planted down.

Dig a hole that’s about two inches deeper than the corm’s height. Place the corm in the hole, cover it with soil, and water well. If you’re planting multiple corms in the same area, space them two to four feet apart.

Planting Transplants

Starting with a pre-sprouted, potted corm is another option. The process is very similar to planting corms, but you don’t have to worry about determining which side of the corm is up and which is down.

Dig a hole that’s the size of the plant’s current container, then place the rootball in the hole. Ensure the top of the rootball is at the soil line, then cover with soil and water well.

How to Grow

Growing ‘Black Magic’ colocasia is simple as long as you know how to provide the proper environment. Keeping the plants warm and moist enough are the two most challenging parts of plant care.

Light

Colocasia plants grow well in partial shade, and ‘Black Magic’ is no exception. The plants can tolerate more sun in northern climates, but they appreciate dappled light or afternoon shade in warmer locations.

If you’re growing these plants indoors, place them near a bright, south-facing or east-facing window. A sunroom always works well if it remains warm during the winter.

Water

‘Black Magic’ colocasia requires consistently moist and damp soil to thrive. If their soil dries out for even a day, the plant’s large leaves will wilt. This is especially true for newly-planted corms that haven’t yet developed much of a root system.

Growing the plants in wet soil is fine; they can even thrive near pond edges and other areas covered with a few inches of water. If you grow them in a drier area, be sure to water them so the soil remains moist. Plan to water a few times a week during the first few months of the plant’s growth and during dry periods.

Fortunately, the plant’s large leaves help shade the ground. This limits evaporation and helps retain moisture, so you can water mature plants less frequently.

Soil

These grow best in rich, loose, and well-draining soil that’s able to hold moisture. High soil organic matter is ideal since it helps hold moisture while also allowing excess water to drain. Mixing a few inches of compost into the soil before planting will raise the organic matter and improve the soil for ‘Black Magic.’

A pH between 5.5 and 6.5 is ideal. Adding sulfur can help lower soil pH, but be aware that it will take multiple months to see a noticeable change in pH.

If you’re growing this colocasia in a container, use a well-draining potting mix that’s high in organic matter. Starting with a soilless potting mix is fine, but you may need to add in extra compost or peat moss to improve the water-holding capacity.

Temperature and Humidity

‘Black Magic’ colocasia likes warm and humid conditions. They grow best when temperatures remain above 65°F (18°C) and the humidity remains high. However, they can tolerate temperatures down to 50°F (10°C) with little damage other than slowed growth.

The above-ground portions of the plants are not frost-tolerant, and the leaves will die back when temperatures dip below 32°F (0°C). The corms will survive light freezes but not prolonged, hard freezes. That’s why they’re hardy down to zone 8.

If you live in zone seven and below, the corms are unlikely to survive the winter outdoors. You can treat the ‘Black Magic’ as an annual and replant the corms each year, or dig up the corms in the fall and keep them indoors until the following spring.

Indoor colocasia grows well at standard household temperatures, but supplying enough humidity can be a challenge. Adding a humidifier will help boost the air moisture to a sufficient level, especially during dry winter days.

Fertilizing

Like all types of colocasia, ‘Black Magic’ requires a large amount of nutrients to remain healthy and produce its large leaves. Enriching the soil with compost and/or worm castings before planting is a good start, but the plants will still benefit from regular fertilization.

Select a balanced fertilizer with an NPK ratio like 10-10-10 or 15-15-15. A granular or liquid fertilizer works well. Apply the fertilizer about once a month in the early spring through the middle of summer. Avoid fertilizing in the fall and winter when growth slows.

Maintenance

‘Black Magic’ requires little maintenance outside of simple pruning.

If you notice leaves that are discolored, diseased, or damaged, you can remove them from the plant to improve appearance and overall plant health. Grab a pair of sharp and sanitized clippers and snip the leaf’s petiole near the base of the plant.

Trimming the leaves after they’re damaged by frost will help improve the plant’s appearance and make it easier to mulch around the underground corm. Use a knife or pair of pruning shears to cut all the leaves about six inches above the base of the plant. Allow the remaining bits of leaves to dry out, then mulch the area to insulate the corm from cold temperatures.

Winter Care 

If you live in zone 7 and below, your plant is unlikely to survive the winter outdoors. Removing the corm and storing it indoors until the following spring allows you to grow the same plant from year to year.

Wait for the first frost to kill the foliage, then dig up the plant’s corms. Trim off any remaining leaves so they’re a few inches above the corm. 

Place your corms in a warm, dry, well-ventilated area out of direct light. A greenhouse works well, as does a warm closet or attic. The corms should be slightly dry within one to two weeks, at which point they’re ready for storage. Place them in peat moss or coco coir and store in a warm, dry place over the winter.

Another option is to dig up the living plants and store them in indoor pots over the winter. If you want to utilize this option, dig up the plants a few weeks before the first frost arrives and place them in a container filled with potting mix. Keep the plants in a bright, warm indoor area until warm weather arrives the following spring.

Propagation

You can propagate ‘Black Magic’ colocasia in numerous ways, but separating the offsets that form along the main corm is the easiest and most reliable method. Dig up your plant and look for tiny, fleshy growths emerging from the main corm: these are offsets. Use a sharp knife to cut them from the rest of the plant.

Place the offsets in a dim, dry area for a few days to allow the cut end to heal. Next, place the offset in a moist, warm environment. A tray filled with moist peat moss, a shallow dish of water, and moist vermiculite all work well.

Check the offset for a sprout every few days. Once you see a sprout, replant into a container filled with moist and well-draining potting mix and move it to a warm and well-lit location.

Pests and Diseases

‘Black Magic’ colocasia experiences few serious pests and diseases, but that doesn’t mean it’s problem-free.

Keep an eye out for taro leaf blight, a disease that causes brown discolorations with distinctive halo-like rings. Remove and dispose of any infected foliage you see to prevent the disease from spreading.

Although somewhat uncommon, insects like armyworms, aphids, and mealybugs can harm ‘Black Magic’ plants. Watch for these pests and remove them as necessary.

Frequently Asked Questions