Royal Hawaiian Black Coral Elephant Ear -2 Gallon

Royal Hawaiian Black Coral Elephant Ear is a bold, clumping tropical perennial grown primarily for its spectacular foliage. The leaves are broadly heart-shaped to arrowhead-shaped with a peltate attachment — meaning the leaf stem inserts near the center of the leaf rather than at the base — which gives each enormous blade a distinctive, slightly cupped, downward-facing angle. The leaf surface has a smooth, matte finish and a deep purple-black to near-black coloration that is among the darkest of any elephant ear available, making it a prized specimen in tropical and bold-texture garden designs. The prominent veining on each leaf adds dimension and visual interest. Petioles (leaf stems) are thick, fleshy, and upright, contributing to the plant's strong architectural presence. The plant grows from a starchy underground corm, which spreads and produces offsets (pups) over time to form an expanding clump. Flowers are rarely produced in ornamental cultivation; when they do appear they consist of a pale yellow-white spadix enclosed in a greenish or yellow spathe, typical of the Araceae family, and they are not considered ornamentally significant. The true spectacle of this plant is entirely its foliage.

Under ideal conditions — rich, consistently moist soil, warm temperatures, and generous fertilization — Royal Hawaiian Black Coral can put on remarkable growth in a single season, easily filling a large container or a substantial section of a tropical-style garden bed. In frost-free zones it may grow even larger over multiple years as the corm mass expands.

Royal Hawaiian Black Coral Elephant Ear is rated for USDA Hardiness Zones 8a through 11b. In Zones 8 and 9 — which includes most of Southern Oregon and Northern California — it can be grown as a root-hardy perennial, with the underground corm surviving mild winters and resprouting each spring once soil temperatures warm. In the warmer portions of Zone 9 and above, foliage may persist nearly year-round or die back only briefly. In Zone 8, some winter mulching over the planting site is recommended to help protect the corm during cold snaps. The plant is very cold-sensitive above ground; foliage will blacken and collapse with the first hard frost. Minimum tolerated temperature for the corm in the ground is generally around 15-20°F with heavy mulch protection. In climates colder than Zone 8, the corm must be lifted after the first frost and stored indoors over winter.

Royal Hawaiian Black Coral performs best in full sun to partial shade. The darkest, most intensely colored foliage is typically achieved in full sun (6 or more hours of direct sunlight per day), which maximizes the production of the dark pigmentation in the leaves. In hotter inland areas of Southern Oregon and Northern California, some afternoon shade can help prevent leaf scorch, especially during the hottest weeks of summer. In shadier conditions the plant will still grow well and produce large leaves, but the foliage color may shift toward a slightly lighter, more greenish-purple tone. Avoid deep shade, which results in leggy growth and a significant reduction in leaf size and color intensity.

This elephant ear thrives in rich, organically amended, consistently moist to wet soils. It is notably tolerant of heavy clay soils and will even grow in poorly drained or occasionally waterlogged conditions — making it an excellent candidate for rain gardens, pond margins, and low-lying areas of the landscape where other plants struggle. For best growth and largest leaf production, amend planting areas generously with compost or other organic matter before planting. Ideal soil pH ranges from 5.5 to 7.0 (slightly acidic to neutral), though the plant is reasonably adaptable to a moderately wide pH range. Unlike many ornamentals, it does not perform well in dry, sandy soils unless those soils are irrigated very consistently and amended with moisture-retaining organic matter.

Consistent moisture is one of the most critical factors in the success of Royal Hawaiian Black Coral. This plant grows natively in moist tropical environments and performs best when the soil is kept evenly moist to wet throughout the growing season. In garden beds, water deeply and regularly — especially during hot, dry periods — to prevent the soil from drying out. Mulching the root zone with 2 to 3 inches of organic mulch helps retain soil moisture between waterings. This elephant ear is highly tolerant of wet soils and standing water, making it well suited for pond edges and bog-style plantings. In containers, watering frequency will be higher; check soil moisture daily during summer and water as soon as the top inch of the mix begins to dry. Avoid prolonged drought stress, which causes leaf curling, browning of leaf margins, and a significant reduction in overall size and vigor.

To achieve the fastest growth and largest, most impressive leaves, fertilize Royal Hawaiian Black Coral regularly throughout the growing season. Apply a balanced, slow-release granular fertilizer (such as a 10-10-10 or similar formulation) at planting time, worked into the soil or container mix. Follow up with a liquid or water-soluble balanced fertilizer every two to four weeks from late spring through late summer. High-nitrogen formulations can encourage especially lush, fast growth but should be balanced with adequate phosphorus and potassium for overall plant health and root development. Container-grown plants require more frequent fertilization than those in the ground, as nutrients leach from the mix with regular watering. Reduce or cease fertilization by early fall as the plant prepares to enter dormancy. Avoid over-fertilizing, which can cause excessive salts to build up in container media.

Royal Hawaiian Black Coral requires minimal pruning. Remove any yellowing, damaged, or dead leaves throughout the growing season by cutting the petiole (leaf stem) cleanly near its base with sharp, clean shears or pruners. This keeps the planting looking tidy and redirects the plant's energy into producing new foliage. No deadheading is needed since the plant is grown primarily for its leaves rather than its flowers. In late fall, after frost kills the above-ground foliage in Zone 8 and colder, cut the dead stems back to ground level and apply a 3 to 4 inch layer of mulch over the planting site to insulate the corm through winter. In Zones 9-11 where the plant remains semi-evergreen or evergreen, simply remove any frost-damaged or weathered leaves as needed to maintain appearance. Divide overcrowded clumps in spring as new growth emerges, carefully separating offset corms from the main clump.

1. Choose a planting site with full sun to partial shade and access to consistent moisture. Locations near water features, low spots in the garden, or irrigated beds are ideal.
2. Amend the planting area with a generous amount of compost or well-aged organic matter, working it into the soil to a depth of at least 12 inches.
3. Dig a planting hole approximately twice the width of the root ball and at the same depth as the plant is growing in its nursery container.
4. Remove the plant carefully from its container, gently loosening any circling roots.
5. Set the plant at the same soil depth it was growing in the container — avoid planting too deep, as this can cause the crown to rot.
6. Backfill with the amended soil, firming it gently around the roots to eliminate air pockets.
7. Water thoroughly after planting, and apply a 2 to 3 inch layer of organic mulch around (but not directly against) the base of the plant to retain moisture and moderate soil temperature.
8. Water regularly until the plant is well established; in Southern Oregon and Northern California, plant out after all danger of frost has passed and soil has warmed, typically from late April through June.

In USDA Zones 8 and 9 (including most of Southern Oregon and the warmer parts of Northern California), the corm can often overwinter in the ground with proper protection. After the first killing frost, cut down the dead foliage and cover the planting area with a 4 to 6 inch layer of straw, bark mulch, or shredded leaves to insulate the corm against hard freezes. Remove the mulch in spring once frost danger has passed. In areas that experience prolonged freezes below 20°F, or for gardeners in Zone 7 and colder, lift the corm after the first frost. Brush off excess soil, allow the corm to dry for a few days, and store it in a cool, dry, frost-free location (around 50-60°F) in a paper bag, cardboard box, or mesh bag filled with peat or vermiculite. Check periodically over winter for signs of rot or excessive drying. Replant outdoors the following spring after the last frost date when soil temperatures reach at least 65°F.

Royal Hawaiian Black Coral makes a spectacular container specimen and is well suited to large pots, planters, and decorative urns on patios, decks, and poolside settings. Use a large container — at least 15 to 20 gallons for a full-sized plant — with adequate drainage holes. Fill with a rich, moisture-retentive potting mix; blending standard potting soil with additional compost and a small amount of moisture-retaining polymer crystals can help maintain the consistent moisture this plant demands. Container-grown plants dry out more quickly than those in the ground, so daily watering may be necessary during summer heat. Fertilize container plants with a balanced liquid fertilizer every two weeks throughout the growing season. Container growing has the additional advantage of making it easy to move the plant to a sheltered location in fall and overwinter it indoors in a cool but frost-free garage, basement, or similar space, allowing gardeners outside the plant's hardy range to enjoy it year after year.

• Specimen or focal point plant: The dramatic dark foliage creates an eye-catching centerpiece in any garden bed or mixed border.
• Tropical-themed gardens: Pairs beautifully with other large-leaved tropicals such as cannas, bananas, gingers, and dahlias to create immersive tropical-style plantings.
• Water garden and pond edge planting: Thrives in moist to wet conditions, making it an outstanding marginal plant at the edge of ponds, streams, and water features.
• Rain gardens and bioswales: Its tolerance of wet and periodically waterlogged soils makes it ideal for stormwater management planting designs.
• Large container displays: Outstanding as a dramatic centerpiece plant in large patio containers, urns, or mixed tropical container arrangements.
• Bold foliage contrast: The near-black leaves provide striking contrast when planted alongside light-colored, chartreuse, or variegated foliage plants.
• Privacy screening: Dense, rapid growth and tall stature provide effective seasonal screening in garden settings.

Royal Hawaiian Black Coral's bold, dark foliage creates the most visual impact when paired with plants that offer strong contrast in color, texture, or form. Excellent companion plant choices include:

• Cannas — especially yellow, orange, or red-flowered varieties — provide dramatic color contrast against the dark leaves.
• Caladiums (white, pink, or red varieties) — offer a delicate, fine-textured counterpoint to the oversized elephant ear leaves.
• Canna 'Pretoria' or other variegated cannas — striped foliage plays off the uniform darkness of Black Coral beautifully.
• Banana plants (Musa spp.) — echo the tropical theme while contributing even more height and varying leaf texture.
• Hibiscus moscheutos (perennial hibiscus) — large, colorful blooms provide flower interest alongside the bold foliage.
• Lantana — bright, multi-colored flower clusters contrast vividly against the dark backdrop of Black Coral's leaves.
• Ginger (Hedychium spp.) — adds fragrant flowers and complementary tropical texture.
• Chartreuse or golden sweet potato vine (Ipomoea batatas) — the lime-green trailing foliage creates a striking color contrast spilling from mixed containers.
• Ornamental grasses — the fine, flowing texture of grasses like Miscanthus or Pennisetum beautifully offsets the coarse, massive elephant ear leaves.

Royal Hawaiian Black Coral Elephant Ear is generally a robust, low-maintenance plant with few serious pest or disease problems. The following issues may occasionally arise:

• Aphids: Clusters of soft-bodied insects may appear on new growth. Knock off with a strong spray of water or treat with insecticidal soap.
• Spider mites: More common in hot, dry conditions. Misting the foliage and maintaining adequate soil moisture helps deter infestations. Treat severe cases with neem oil or insecticidal soap.
• Slugs and snails: May feed on young, emerging leaves, particularly in cool and damp spring conditions. Use iron phosphate baits or other slug controls around the base of plants.
• Root rot (Phytophthora, Pythium): Can occur if the corm sits in poorly aerated, stagnant water. This is more of a risk in heavy containers without drainage. Ensure containers have drainage holes and the planting medium does not become anaerobic.
• Leaf spot: Fungal leaf spots may appear during prolonged wet, humid periods, though this is rarely severe. Improve air circulation and avoid overhead watering when possible.
• Deer and rabbit resistance: The plant is considered deer and rabbit resistant due to calcium oxalate crystals present in all plant tissues.

All parts of Colocasia esculenta 'Black Coral' contain calcium oxalate crystals and are considered toxic if eaten raw. Ingestion of raw plant material can cause intense oral irritation, pain and swelling of the mouth, tongue, and lips, excessive drooling, difficulty swallowing, and vomiting. These symptoms are caused by the sharp calcium oxalate crystals that penetrate soft tissues. The plant is considered toxic to humans, dogs, cats, and horses when ingested raw. Contact with the sap may also cause mild skin irritation in sensitive individuals; wearing gloves when handling the plant, especially when dividing corms or cutting stems, is advisable. Keep this plant out of reach of children and pets. Note that the corm of Colocasia esculenta is the source of the widely consumed food crop taro — but toxicity is fully neutralized only through thorough cooking.

Royal Hawaiian Black Coral delivers its primary ornamental display from late spring through the first hard frost of autumn. As soil temperatures warm in spring, the corm sends up tightly furled new leaves that unfurl dramatically into their full, oversized, near-black magnificence. Growth accelerates rapidly through the warm months of summer, when the plant puts on its most impressive display of bold, dark tropical foliage. The deep purple-black color is at its most intense under full sun during summer. As temperatures cool in early fall, growth slows and the foliage may begin to look less vigorous; the plant typically enters dormancy after the first hard frost. In frost-free climates (Zone 10-11), the plant may remain semi-evergreen or evergreen year-round. The dramatic foliage provides bold textural contrast in the summer and early autumn landscape, making it a valuable seasonal counterpoint to flowering annuals and perennials throughout the warm season.