Bougainvillea 'Adarna' (Shikendari): Multicolour Bract Care Guide

Overview

Bougainvillea 'Adarna', also known as Shikendari, is one of the most visually dramatic and highly sought-after bougainvillea cultivars in South and Southeast Asian collector circles. Named to evoke the legendary Adarna bird of Filipino folklore — famous for its shifting, iridescent plumage — this cultivar lives up to its name with bracts that morph between warm yellow, deep orange, and vivid pink-magenta splashes, often on the same plant simultaneously. With origins tied to both Indonesia and China, it has become a staple in Indian tropical gardens for its exceptional vigour, repeat-blooming reliability, and the added prestige of its Moonlight (white-tinged foliage) and variegated leaf forms.

Like all bougainvilleas, Adarna is fundamentally a 'bloom-on-stress' plant. It does not reward pampering. The key to triggering its most spectacular colour display is understanding how to balance sun, water stress, and lean fertilization. Overwater it in a shaded spot and it will produce a wall of lush green leaves and almost no bracts. Give it relentless direct sun, deliberately dry periods between deep waterings, and the occasional pruning, and it will reward you with near-continuous colour almost year-round in Indian conditions.

Light

Full, direct sunlight is non-negotiable. Adarna needs a minimum of 6 to 8 hours of unobstructed direct sun every single day. More is better. In Indian conditions, a south- or west-facing outdoor position is ideal. The intensity of its multicoloured bract variation is directly tied to sun exposure — plants in full sun produce the most vivid colour shifts, while those in partial shade revert toward dull, washed-out tones and stop blooming prolifically. This plant cannot be successfully grown as an indoor Bougainvillea.

Temperature

Adarna thrives in the warm, humid conditions found across tropical India. It handles intense heat well (up to 40°C / 104°F) and actively blooms through Indian summers. It is frost-sensitive and will die back or be killed by sustained temperatures below 10°C (50°F). In the plains of India, it can be treated as a permanent outdoor perennial with year-round growth.

Humidity

It tolerates a wide humidity range and handles the high humidity of Indian monsoon seasons well, provided the soil drainage is excellent. The danger period is the monsoon, when combined high humidity and waterlogged soil accelerates root rot. Elevate containers during heavy rain periods or move them under a sheltered overhang to manage excess water.

Watering: The Stress-Watering Method

This is the single most important technique for getting Adarna to bloom prolifically: water deeply, then allow the soil to dry out completely before watering again. Bougainvillea evolved in seasonally dry South American forests and uses dry periods as its biological trigger to shift energy from leaf production into flowering. In practice, check the top 1 to 2 inches of soil — only water when it is completely dry to the touch. Apply water slowly and deeply until it runs freely from the drainage holes, then stop and do not water again until the soil dries. For containers, never leave the pot sitting in a saucer of standing water. During active bloom cycles, extend the dry-down period further — a 3 to 4 week deliberate dry spell before resuming watering is a proven method to initiate a heavy new flush of bracts.

Soil

Excellent drainage is the most important soil property. A mix of loamy garden soil, coarse river sand, and perlite (roughly 50:30:20) works well for containers. Pre-made cactus or succulent mixes amended with some compost are also suitable. Avoid heavy, water-retentive soils. In-ground planting on slightly raised beds or slopes is ideal to prevent monsoon waterlogging.

Fertilizer

Adarna is a heavy feeder during active growth. Use a balanced NPK fertilizer (10-10-10 or 20-20-20) every two to four weeks during spring and the post-monsoon growing season. When you want to trigger or intensify a bloom flush, switch to a high-phosphorus and high-potassium formula (such as 10-30-20) and reduce nitrogen, as excess nitrogen directs energy into leafy growth at the expense of bracts. Always water the soil before applying fertilizer to avoid root burn. Organic options include compost tea, well-rotted cow manure, and banana peel water for potassium supplementation.

Pruning

Bougainvillea bracts form on new lateral shoots that emerge from mature canes, not on old woody growth. Regular pruning is therefore directly tied to bloom production. After each bloom flush fades, tip-prune the lateral shoots to just above a leaf node. This stimulates branching and the development of multiple new flowering shoots. For a trellis or fence application, train 4 to 6 main framework canes horizontally or diagonally — horizontally-trained canes produce far more laterals (and therefore more blooms) than vertical ones. A harder structural prune can be performed in early spring before the main growing season begins. Always wear thick gloves; Adarna's thorns are substantial, and the sap is a skin irritant.

Propagation

Propagate from semi-hardwood stem cuttings taken from pencil-thick stems with 4 to 6 leaves. Cut just below a leaf node to a length of 4 to 6 inches, strip the lower leaves, and dip the cut end in rooting hormone powder. Insert into a fast-draining propagation mix of perlite and peat. Keep barely moist — never wet — in a warm spot with bright indirect light. Roots typically develop in 4 to 8 weeks. Notably, Adarna occasionally produces viable seeds that can be successfully germinated, an unusual trait for a premium hybrid cultivar.

Toxicity

Bougainvillea sap can cause contact dermatitis — skin redness, itching, and rash — on direct contact in sensitive individuals. Always wear gloves when pruning. The plant material is mildly toxic to cats and dogs if ingested, potentially causing drooling, vomiting, or gastrointestinal upset. This is not a pet-safe plant.

Common Problems

The most frequent problem is root rot from overwatering or poor drainage, especially during the Indian monsoon. If the plant collapses, check the roots — brown, mushy roots confirm rot; cut back to healthy tissue and repot in fresh, dry, well-draining mix. Yellowing leaves between the veins (interveinal chlorosis) typically indicates iron or magnesium deficiency, common in alkaline soils — treat with iron chelate or a micronutrient feed. Lush green growth with no bracts almost always means either too little sunlight or too much nitrogen fertilizer. Aphids, mealybugs, and spider mites are the most common pest threats; treat promptly with neem oil spray.