Dictamnus are hardy perennials that are ideal to use in the middle of a border as they are about 90 cm in height.
They usually come into bloom from the end of spring to the summer, and carry star shaped pink or white flowers.
Dictamnus has fragrant green leaves. Some of the common names for members of the Dictamnus genus include Gas Plant, False dittany, and Burning bush.
Dictamnus albus Photograph by Nuu..ul, CC.
Gas Plant by magnolia1000, CC.
Common Names: Burning Bush, False Dittany, White Dittany, Fraxinella, Gas Plant.
Life Cycle: Hardy perennial.
Height: 24 to 36 inches (60 to 90 cm).
Native: Southern Europe, North Africa, Asia
Growing Region: Zones 3 to 8.
Flowers: Late spring through to summer.
Flower Details: White, pink, pale purple. Striped. Star-shaped. Terminal spikes.
Foliage: Herbaceous. Green. Glossy. Ash-like. Fragrant; lemon smell.
Sow Outside: Cover seed. Autumn. Spacing 24 to 36 inches (60 to 90 cm).
Sow Inside: Germination time: one to six months. May require several rounds of refrigeration. Seeds should first be sown into flats, next wrap in a plastic bag, then stratify by refrigeration for four to six weeks. Next bring to a temperature of 60 to 65°F (16 to 18°C). Hopefully seedlings should emerge within two months, if not then place back into the fridge for a further four to six weeks, before returning to the higher temperature. If seedlings emerge before the second round of refrigeration is over then remove the flat from the fridge. Transplant outdoors following the last frost or in autumn. Dig deep hole and add in lots of compost.
Requirements and care: Full sunlight or partial shade. Soil pH 5.5 to 7.0. Can survive in rich, dry soils. Poor soil if moist. Regular watering to keep poor soils moist. Prune following flowering in hot areas. In autumn cut back stems. Supply a winter mulch. Propagate: from seed.
Miscellaneous: The Dictamnus plant produces flammable oils that have a very volatile nature. This means that they and the surrounding air sets fire very easily, hence the common name of Burning Bush.
It is best to sow Dictamnus seeds in the autumn in either a sunny or lightly shaded part of the garden that is moist and slightly acidic to neutral (pH 5.5 to 7). The seeds should be sown about 40 to 60 cm apart, and lightly covered with topsoil.
If first growing gas plants (Dictamnus) indoors then the seeds should be imbibed by placing the seeds (within soil) in a black plastic bag, left for a fortnight at 16°C, then placed in the fridge for four to six weeks. The germination should then proceed at a temperature of 16 to 17°C. It may be necessary to have cycles of refrigeration and warmth for germination to occur. Seedlings of Dictamnus should then be put out in deep holes at the end of autumn.
It will typically take about four years until the gas plant will flower. Dictamnus should be cut back at the stems every autumn.
I hope that you enjoyed this guide on how to grow Dictamnus plants. Updated September 2020.