Acacia mangium – Mangium

Description

Acacia mangium – Mangium / Broadleaf Salwood

Family: Fabaceae
Packet Size: 30 seeds

Description

Acacia mangium, also called Mangium, Broadleaf Salwood or Black Wattle, is a fast-growing Australian native tree from tropical northern Queensland. Its large, glossy-looking green leaves and often relatively straight trunk give it a very different appearance from fine-leaved wattles.

The tree produces pale cream flower spikes rather than golden round flower heads. Mature seed pods twist or coil and contain dark seeds with conspicuous orange-yellow seed coatings. In suitable tropical conditions it can become a large tree, making it best suited to substantial properties.

Key Features

• Flowers: Loose cream to white cylindrical spikes, rather than round flower balls.
• Foliage: Broad, asymmetrical green leaves with three to five obvious lengthwise veins.
• Habit: Fast-growing tropical tree, potentially 7–30 m high in favourable sites.
• Garden uses: Tropical shelter, larger-scale plantings and timber-oriented landscapes where appropriate.

Growing Conditions

• Position: Full sun with room to establish an extensive crown and root system.
• Soil: Adaptable to a range of soils; ensure the site does not remain waterlogged.
• Watering: Regular moisture while young supports establishment, especially in hot periods.
• Climate: Best suited to warm tropical and frost-free conditions.
• Management: Avoid planting close to structures or confined garden beds; allow for eventual tree height.

Seed Propagation

• Prepare: Wattle seeds usually have a hard seed coat. Carefully nick the coat or gently rub one side with fine sandpaper, avoiding the embryo. Soak in room-temperature water for about 12–24 hours before sowing.
• Sow: Place seeds about 5 mm deep in moist, freely draining seed-raising mix.
• Position: Keep in a warm, bright, sheltered position, away from harsh afternoon sun while seedlings are small.
• Moisture: Keep the medium evenly moist but not waterlogged.
• Germination: Germination varies with seed age, temperature and nicking or scratching the seed coat. Allow additional time if some seed coats remain firm.
• Transplant: Move seedlings into individual pots once they have true leaves and can be handled safely.

Growing Note: Mangium is planted widely outside its natural range and can naturalise in suitable tropical environments. Consider local planting restrictions and nearby natural habitats.