The Phaius tankervilleae, commonly known as the Nun’s Orchid, is a terrestrial orchid native to tropical Asia and the Pacific Islands. It is cherished for its robust growth and striking beauty of its blooms. Its common name comes from the hood-like shape of its petals, which resemble a nun’s habit. This adaptable orchid is a rewarding and visually appealing houseplant for indoor gardens.
Essential Care Requirements
Providing the right light is important for the Nun’s Orchid’s health. The plant thrives in bright, indirect light, mimicking its natural dappled sunlight under a tree canopy. An east-facing window provides ideal morning sun. South or west-facing windows work if light is filtered to prevent leaf scorch. Too much direct sun causes yellowed or burned leaves, while insufficient light results in leggy growth and no blooms.
Proper watering practices are important for the Nun’s Orchid’s well-being. Allow the potting medium to dry slightly between waterings, typically when the top inch or two feels dry to the touch. Water thoroughly until it drains from the pot’s bottom. Avoid standing water in the saucer, as constant wetness leads to root rot. Rainwater or distilled water is preferred, as these plants are sensitive to the salts and chemicals found in tap water.
Maintaining appropriate temperature and humidity levels contributes to a thriving Nun’s Orchid. During the day, temperatures between 65°F and 80°F (18°C-27°C) are suitable, with a slight drop to 60°F-65°F (15°C-18°C) at night. These orchids appreciate 50% to 70% humidity. In drier indoor environments, use a pebble tray (ensuring the pot does not sit in water) or a room humidifier to elevate ambient moisture.
A well-draining, coarse orchid mix is necessary for root health and overall growth, allowing for proper aeration and preventing waterlogging. A suitable blend includes fir bark, perlite, and charcoal, providing excellent drainage and airflow around the roots. Some growers add a small amount of peat moss or coco coir to retain minimal moisture while ensuring good drainage. The coarse texture ensures roots receive adequate oxygen.
Fertilize regularly for robust growth and flowering. During the active growing season (spring through fall), apply a balanced orchid fertilizer (e.g., 20-20-20) diluted to half or quarter strength every two to three weeks. Reduce frequency and strength in winter when growth slows. This prevents salt buildup, which can harm roots.
Repotting Your Nun’s Orchid
Repotting is necessary when the plant outgrows its container or the potting medium decomposes. Signs include roots emerging from drainage holes, the plant becoming top-heavy, or the mix breaking down and retaining too much moisture. Repotting is best performed after flowering, usually in spring, allowing the plant to establish before the next growth cycle.
When repotting, carefully remove the orchid and gently shake off old potting medium. Inspect roots, trimming any soft, mushy, or rotted ones with sterilized tools. Place fresh potting mix at the bottom of a new pot, one or two sizes larger. Center the plant, spread roots, and fill with fresh medium, gently tapping to settle. Avoid compacting the mix too tightly, as this hinders aeration.
Encouraging Glorious Blooms
To encourage blooms, provide a slight temperature differential between day and night, typically a 10-15°F (6-8°C) drop. This fluctuation, especially in cooler months, helps initiate flower spikes. Sufficient light is also important, as inadequate light is a common reason for no flowering.
Once a flower spike emerges, avoid drastic environmental changes to prevent bud blast. Blooms appear in late winter to early spring, lasting several weeks, with vibrant white, brown, and purple color combinations. Consistent watering and humidity during blooming prolong flower vibrancy. After blooms fade, cut the spent spike at its base.
Troubleshooting Common Issues
Yellowing leaves can indicate several issues. Overwatering is a common cause, leading to root rot that prevents nutrient absorption, causing foliage to yellow and soften. Dry conditions or insufficient watering can also cause leaves to yellow and become crispy. A nutrient imbalance, like nitrogen deficiency, can also cause generalized yellowing across older leaves.
If your Nun’s Orchid fails to bloom, it is often due to insufficient light or lack of a cool period. Without adequate bright, indirect light, the plant may not accumulate enough energy to flower. If it does not experience the recommended night temperature drop in cooler months, it may not initiate flower spike development. Adjusting light and temperature can resolve this.
Root rot is a common problem caused by overwatering and poorly draining potting medium. Symptoms include yellowing leaves, plant decline, and soft, mushy roots with a foul odor. To address it, remove the plant, trim affected roots with sterilized scissors, and repot in fresh, well-draining medium. Adjust your watering schedule to allow the mix to dry more between applications.
Pests are not frequent but can affect Nun’s Orchids. Mealybugs appear as small, white, cottony masses, while scale insects appear as small, hard, brown bumps. Both feed on plant sap, causing stunted growth and sticky residue. Treat infestations by wiping pests with a rubbing alcohol-dipped cotton swab or applying insecticidal soap. Repeat applications may be necessary to eradicate them.