Dictamnus albus [dik-TAM-nus, AL-bus] is an herbaceous perennial, native to warm woodlands of southern Europe, Asia, and northern Africa belonging to the family Rutaceae.
The plants come back every year and it is the only species in the Dictamnus genus but has many geographical variants.
Dictamnus albus has a few different common names including:
- Gas plants
- Burning bush
The name burning bush and gasplant are derived from the volatile oils the plant produces, which catch fire rapidly in extremely hot weather.
This quality leads to comparisons with the burning bush mentioned in the Bible.
Dictamnus Albus Care
Size & Growth
Even though Dictamnus albus is easy to grow, it does take its sweet time. It can take up to 3 to 4 years to flower.
However, it is visually interesting, long-lived, and easy to maintain.
Under the right growing conditions, plants reach 2’ – 3’ feet high and 1.5’ – 2.5’ feet wide.
The gas plant grows upright forming clumps of rigid vertical stems.
The foliage is made up of glossy odd-pinnate leaves. They are light green and emit a lemony scent when rubbed or crushed.
Flowering and Bloom Time
Besides its flammable, volatile oils, gas plants are known for their showy flowers.
These flowers might lack the lemony scent the leaves have but are very aesthetically pleasing and why it is considered as an ornamental plant.
The flowers have five petals, each along with long projecting stamens.
Together, the flowers form a loose pyramidal spike, which is very interesting visually.
Each flower is about 1” inch long and blooms in late spring to early summer.
Depending on the variety, they can vary in colors, including white, pink, red, and lilac.
Light & Temperature
Dictamnus albus prefers colder temperatures and grow strong in USDA zones 4 to 9.
They do the best in northern climates where the nights are significantly cooler.
In very hot temperatures, there is a risk of the volatile oils becoming active and igniting.
As for light, Dictamnus albus does not like even partial shade. It needs full sun to grow well.
When planting in your garden or as a specimen, choose a sunny location where the sun shines for at least 6 hours every day.
Watering and Feeding
Dictamnus plants love water and thrive in moist soil and does not tolerate droughts unless it’s fully established.
However, you have to be careful about overwatering.
When the weather gets very cold, spread the watering schedule to avoid making the soil too soggy.
Before watering, check the soil to ensure it is dry before dousing it with a small amount of water.
Soil & Transplanting
The gasplant doesn’t have specific soil requirements.
It thrives in most types of soil and succeeds easily in ordinary garden soil.
However, it’s best kept away from heavy and damp soils.
Choose a medium, well-drained soil which is fairly fertile and humusy.
It’s important to keep the soil moist but preventing it from becoming too soggy.
As for transplanting, it is best avoided for this species as it doesn’t like being disturbed.
Do it when the Dictamnus is only a seedling, but you have to be extremely delicate with it.
Grooming and Maintenance
Dictamnus is best left undisturbed as the roots don’t like being tampered with.
The only maintenance this plant requires is deadheading, occasional removal of dead leaves, and regular watering.
It is fairly low-maintenance and doesn’t need much attention during its lifespan.
How to Propagate Gas Plant
Dittany is best propagated with seeds.
- Seeds are sown in a cold frame soon after they ripen in spring.
- It takes the seeds one to six months to germinate properly at 59° degrees Fahrenheit (15° C).
- When they are strong and large enough to be handled, prick the seedlings into individual pots.
- Let them develop inside a greenhouse during the first winter.
- Move them to their permanent positions in late spring or early summer.
The plant is also propagated by division in the springtime but requires extra care.
- This is important because the plant does not react well to root disturbance.
- Gently tease out divisions from the side, avoiding digging the main clump.
- Look for divisions that already have formed roots and pot them in a greenhouse for at least a year.
Gas Plant Pest or Diseases
Dictamnus albus does not have any serious pest and disease problems you need to worry about.
- However, the plan does have some toxicity.
- The leaves could irritate the skin when touched under the sun.
- Contact with the foliage may lead to phytophotodermatitis.
- The leaves have a strong bitter and unpalatable taste.
- Even though they have a lemon-like scent, the plant is acrid when ingested.
- In some cases, the consumption has caused a mild upset stomach.
Dictamnus Albus Uses
Dictamnus is a beauty to look at. The ultimate use of this species is in cottage gardens among other flowering plants such as daylilies, peonies, iris, and campanulas to accompany the blooms.
It also looks pretty lined up along borders in gardens and along walls.
Besides garden uses, Dictamnus albus is also used to extract various constituents.
Around 100 chemical compounds have been isolated from the plant, including phenylpropane, coumarins, flavonoids, alkaloids, and more.
The volatile oils in the plant are also used in isoprene.