Dictamnus Albus

I feel that gas plant is one of the most underappreciated and underutilized perennials in our gardens. Having stated this fact, I’ll mention that this plant also keeps me on my toes for reasons I’ll mention shortly. While slow to establish, this perennial is very long lasting in the garden and is virtually pest and disease free. Combine those traits with the merits of the aromatic foliage and beautiful flowers, it seems like this perennial should be in more garden centers and home gardens.

Native to warm, open woodland habitats in southern Europe, northern Africa and much of Asia, Dictamnus albus (Rutaceae family) prefers full sun or the lightest of shade. The rigid, vertical stems are late to emerge but quickly form a bushy, upright, mounded plant that matures to 36 inches tall with glossy green, pinnate leaves that have a citrus scent. Be wary of the oils associated with this plant as the foliage can cause phytophotodermatitis in some individuals (including me!). My literally “brush” with this beautiful plant resulted in a poison ivy-like rash and mild agony. Be wary! Wear gloves and other protective equipment when interacting closely with this plant. Not surprisingly, deer and other critters don’t find this plant palatable.

The loose, fragrant, pyramidal flower spikes arrive in late spring to early summer and feature spider-like, five-petaled flowers that last for two to three weeks. The star-shaped seed pods that form later are also quite ornamental. The straight species features white flowers, although the selections ‘Purpureus’ and ‘Rubra’ feature prominent, maroon veins on the petals and more hints of pink in the flowers. The common name, “gas plant,” comes from the interesting attribute of this plant to be ignited (literally) under certain circumstances. The highly volatile oils of this plant, combined with a still, hot summer night and fire source may result in a quick “poof” of flame that, while not harming the plant, dissipates quickly. I’ve failed this experiment many times but there are some YouTube videos out there that will blow your mind.

Gas plant prefers evenly moist, fertile and well-drained soils on the alkaline side if possible. Drought tolerant once established, they absolutely will not thrive in heavier, waterlogged soils. This plant does develop a taproot, so select a permanent location as they are best left undisturbed. Division, if required, is best achieved in autumn along the sides of the woody root system to “tease” out chunks with roots that should be immediately potted or planted in place. Propagation is best by seed (cold stratified) although it will take new plants three to five years to bloom from seed. This delay in getting to “saleable size” from seedlings may be one of the factors associated with its rareness in retail.

Specifics:

Name: Dictamnus albus (‘Purpureus’ and ‘Rubra’ are common varieties)

Common names: gas plant, dittany, fraxinella and burning bush

Description: Late to emerge, glossy, aromatic, pinnate foliage fills out and is quickly followed by beautiful, late spring/early summer flower spikes in colors ranging from white to pink and rose.

Hardiness: USDA Hardiness Zones 3-8

In the landscape: This stalwart perennial is excellent in the mixed border, cottage garden scheme and as a specimen plant. Gas plant has also found use on sunny slopes and used in tandem with other pollinator-friendly plantings.