Saptaparni (Blackboard Tree)
Alstonia scholaris
📖 About this plant
Saptaparni (Alstonia scholaris), also known as the Blackboard Tree, Indian Devil Tree, Devil Tree, or Chatian, is a large evergreen tree native to the Indian subcontinent and Southeast Asia, widely planted across India as an avenue and shade tree. The common name “Saptaparni” in Sanskrit means “seven leaves” — referring to the distinctive arrangement of leaves in whorls of 6-8 (usually 7) around each node, like the spokes of an umbrella. The common name “Blackboard Tree” comes from the use of the wood for making blackboards and writing slates in earlier times. The tree produces small, greenish-white, intensely fragrant flowers in dense umbrella-like clusters from October to December — the bloom fills the evening air with a sweet, gardenia-like fragrance that is a marker of autumn across Indian cities. However, the strong fragrance can be overwhelming for some people and has led to folk beliefs associating the tree with ghosts (hence “Devil Tree”). Beyond ornamental value, Saptaparni is an important medicinal plant in Ayurveda — the bark is used to treat fever, malaria, digestive disorders, and respiratory conditions. Modern research has confirmed antimalarial, antibacterial, and anti-inflammatory properties (the bark contains the alkaloid ditamine). The wood is used for furniture, packing cases, and plywood. The tree is highly adaptable — it thrives in poor soils, drought, and urban pollution, making it a popular choice for city planting. However, the tree has aggressive roots and should be planted away from foundations and pavements.
🧑🌾 Care requirements
Full sun to partial shade
Weekly (drought-tolerant once established)
Moderate to high (50-80%)
15-38°C
Well-draining loamy soil; tolerates poor soils. pH 5.5-7.5
Balanced NPK or compost 2-3 times per year
🌐 Common Names
📋 Plant facts
- 🌍 Origin
- Indian subcontinent, Southeast Asia, and southern China
- 📏 Max height
- 15-40 m (typically 12-20 m in cultivation)
- 📐 Spread
- 6-12 m
- 🕰️ Bloom time
- October to December (autumn to early winter in India)
- 🎨 Bloom color
- Small greenish-white fragrant flowers in dense umbrella-like clusters
- 🍃 Foliage color
- Dark green, glossy, leathery leaves in whorls of 6-8 around each node
- ⏳ Lifespan
- 50-100+ years
- 📈 Growth rate
- Fast — 1-2 m per year when young
- ☠️ Toxicity
- Mildly toxic — bark and latex contain alkaloids; keep away from pets and children. Used medicinally under guidance.
- 🌱 Propagation
- Seeds (germinate in 2-4 weeks), stem cuttings
🛡️ Health & Safety
Mildly toxic — bark and latex contain alkaloids; keep away from pets and children. Used medicinally under guidance.
Common issues
- Leaf-eating caterpillars, scale insects, aphids, leaf spot diseases, root rot from poor drainage, sooty mold from aphid honeydew
- overall relatively pest-resistant
💡 Care tips
- Plant in full sun to partial shade with 8-10 m spacing — Saptaparni becomes a large tree.
- The tree is highly adaptable and tolerates poor soils, drought, and urban pollution — perfect for city planting.
- Water regularly during the first 2-3 years to establish
- afterwards it is drought-tolerant.
- Apply compost or balanced fertilizer 2-3 times per year.
- Prune young trees to develop a strong central leader
- mature trees need only light pruning to remove dead wood.
- Avoid planting near foundations, pavements, or underground pipes — the tree develops aggressive roots.
- Trees start flowering in 5-7 years from seed.
- Plant Saptaparni as an avenue tree, shade tree, or specimen tree in large gardens and parks.
- The tree is evergreen and provides year-round shade.
- The fragrant flowers appear in autumn (October-December) and fill the evening air with a sweet scent — plant away from bedroom windows if the fragrance is overwhelming.
- The tree is suitable for Indian cities and is widely planted in Delhi, Mumbai, Bangalore, and Chennai.