Dictamnus albus var. purpureus, commonly known as Purple Burning Bush or Gas Plant, is a remarkable hardy perennial with elegant flower spikes, attractive foliage and a fascinating botanical history.
In late spring and early summer, upright stems carry delicate pale pink flowers with striking dark purple veins and prominent stamens. Rising above glossy green foliage, these beautifully patterned flowers make an unusual and eye-catching addition to cottage gardens, naturalistic planting schemes and perennial borders.
Its intriguing common name comes from the volatile aromatic oils released by the plant, which can produce flammable vapours during particularly hot weather. This unusual characteristic has earned it the name Burning Bush.
A long-lived perennial, Dictamnus prefers a sunny position in well-drained soil. Once established, it is relatively drought tolerant and can remain in the same position for many years. It dislikes root disturbance, making it particularly suitable for permanent planting schemes.
Growing Dictamnus from seed requires patience, as germination involves warm and cold stratification and plants may take several years to reach flowering maturity. However, its exquisite flowers and unusual history make it a rewarding plant for experienced gardeners.
Important Safety Information: Dictamnus can cause phytophotodermatitis. Contact with the plant followed by exposure to sunlight may cause painful skin irritation and blistering. Always wear gloves and long sleeves when handling, and position plants away from paths or areas where accidental contact is likely. Do not attempt to ignite the plant.
When to Sow: Sep - Dec. Autumn sowing is recommended to allow seeds to experience natural seasonal temperature changes.
HOW TO SOW: Sow in Autumn into pots or deep modules filled with a free-draining seed compost. Cover lightly with compost or fine grit and water gently. Leave in a sheltered cold frame to experience natural seasonal changes. Germination can be irregular, and some seeds may not emerge until the following year. Do not discard ungerminated pots too early.
Classification: Hardy Herbaceous Perennial
Expert Level: Requires Experience
Germination Time: Approximately 15–20 weeks, sometimes longer.
Flowering Time: May - Jun
Site: Full sun or partial shade. Choose a permanent position away from paths and areas where accidental contact with the foliage is likely.
Soil Type: Moderately fertile, well-drained soil. Avoid waterlogged conditions, particularly during winter.
Soil Acidity: Acid, neutral or alkaline.
Moisture: Keep compost consistently but lightly moist during germination. Water young plants regularly during establishment. Once established, plants are relatively drought tolerant and dislike waterlogged soil.
Care: Transplant seedlings carefully into individual pots once large enough to handle. Plant into their permanent position when well established, avoiding unnecessary root disturbance. Dictamnus develops a substantial root system and dislikes being moved once established. Water during prolonged dry spells while young. Mature plants require little maintenance. Cut back dead stems in autumn, wearing protective clothing. Plants may take several years to reach flowering maturity.
WARNING: Always wear gloves and long sleeves when handling Dictamnus. Contact with the foliage or sap, followed by exposure to sunlight, can cause painful skin irritation. Symptoms may be delayed. Avoid planting where children or pets may brush against the foliage. Do not attempt to ignite the plant.
Use: Cottage gardens, perennial borders, architectural planting and pollinator-friendly gardens. Particularly suitable for permanent planting schemes where its unusual flowers can be admired without frequent handling.
Days to Maturity: Approximately Year 3 - 4 for first flowering.
Height: 80–90 cm.
Plant Spacing: 80 cm.