The Hoya lacunosa ‘Mint Coin’, also known as ‘Silver Mint Coin’, is a highly sought-after cultivar of the Hoya genus, a group of epiphytic vines native to Southeast Asia. This plant is prized for its small, compact growth habit and uniquely textured foliage. The leaves are concave, a characteristic known as lacunose, and are often rounded like a small coin. Unlike the standard green Hoya lacunosa, this variety features soft, silvery-mint variegation across its matte green leaves. This trailing plant is a manageable addition to an indoor collection, rewarding growers with distinct appearance and clusters of cream-colored, star-shaped flowers that often release a pleasant, cinnamon-like fragrance.
Establishing the Ideal Habitat
The health and unique coloration of your Hoya lacunosa ‘Mint Coin’ depend heavily on recreating the tropical conditions of its natural environment.
Light
To maintain the striking silver-mint tones, the plant requires consistent bright, indirect light. Optimal placement is near an east or west-facing window, or several feet away from a sunny south-facing window. Insufficient light causes sparse growth and the loss of the distinctive silver sheen. Direct, intense sunlight can scorch the delicate leaves, resulting in permanent burn marks.
Temperature
This species thrives in typical indoor temperatures, ideally maintaining a range between 65°F and 85°F (18°C and 29°C). Consistent warmth supports active growth, especially when light levels are adequate. Protect the plant from extreme temperature fluctuations and cold drafts, such as those near external doors or air conditioning vents. Temperatures dropping below 55°F (13°C) can cause significant stress and damage.
Humidity
As a tropical epiphyte, the ‘Mint Coin’ benefits from elevated ambient moisture, preferring humidity levels between 40% and 60%. While it tolerates average household humidity, higher levels encourage faster growth and prevent leaf edges from crisping. Humidity can be increased by grouping the Hoya with other houseplants to create a localized microclimate. Alternatively, place the pot on a shallow tray filled with water and pebbles, ensuring the pot bottom does not touch the water.
Routine Substrate and Nutrient Care
Proper physical maintenance is crucial for preventing common Hoya ailments, particularly those related to moisture retention.
Watering
The most common mistake in Hoya care is overwatering, which leads to fatal root rot. Water the plant thoroughly only once the top one to two inches of the potting medium have become completely dry. Use the “soak and dry” method: water until it runs freely from the drainage holes, then discard any excess water collected in the saucer. Reduce the frequency of watering significantly during the winter months to match the decreased moisture demand.
Soil Composition
Because this Hoya grows naturally on trees, it requires an extremely well-draining and airy substrate mixture. Standard, dense potting soil retains too much moisture and suffocates the roots. Use a specialized epiphytic mix, combining components like orchid bark, perlite, and coco coir to ensure excellent aeration and drainage. This chunky composition allows for rapid water runoff while still holding enough moisture for the roots to access.
Fertilization
During the active growing season of spring and summer, the plant benefits from a regular feeding schedule to support new foliage and flower production. Apply a balanced, water-soluble houseplant fertilizer once a month, diluted to one-quarter to one-half the recommended strength. Over-fertilizing can lead to a buildup of salts and potentially burn the roots, so always use a weak solution. Cease all fertilization during the fall and winter months.
Multiplying and Protecting Your Plant
Knowing how to safely increase your collection and manage potential issues will help ensure your plant’s longevity.
Propagation
The most reliable method for multiplying Hoya lacunosa ‘Mint Coin’ is through stem cuttings. Select a healthy vine and cut a section that includes at least two leaf nodes, ensuring the cut is taken just below a node. Cuttings can be rooted in various mediums, including moist sphagnum moss, perlite, or directly in a chunky Hoya potting mix. Keeping the cuttings in a high-humidity environment, such as a sealed clear container, will speed up root development.
Troubleshooting
Preventing root rot is the primary disease concern, managed by following proper watering and soil composition guidelines. Fungal issues can develop in conditions with high humidity and poor air circulation, so ensure gentle airflow around the plant. Pests such as mealybugs and scale are the most common insects affecting Hoyas. These are identified by small, cottony white masses or tiny brown bumps on the stems and undersides of the leaves. Treatment involves gently wiping the affected areas with a cotton swab dipped in rubbing alcohol to physically remove the pests.