Sweet wormwood
Artemisia annua · Asteraceae
The gardener's calendar
Ideal time to plant sweet wormwood: set it out when the soil is neither frozen nor waterlogged, and water generously as it establishes.
ID card
- Foliage
- Deciduous
- Flowering
- August to October, pale yellow flowers
- Adult size
- 60 to 150 cm in height
- Growth
- Fast
- Hardiness
- Frost-tender, low hardiness
- Origin
- China, now cosmopolitan
- Soil type
- Well-drained, dry to moderately moist
Care
Sunlight
Place annual artemisia in full sun for optimal growth and better content of active compounds. It tolerates partial shade as well, but will develop a less compact form. Avoid heavily shaded areas and locations exposed to strong winds.
Watering
Water regularly during the first year of establishment to promote rooting. Once established, this plant needs little water and prefers periods of moderate drought. Reduce watering in late summer to prevent excessive moisture.
Soil and preparation
Annual artemisia thrives in well-drained, poor to moderately fertile soil. No specific fertilizer is needed; soil enriched with compost at planting time is quite sufficient. Avoid compacted soils and waterlogged areas.
Pruning and maintenance
Prune lightly after flowering to rejuvenate the form and encourage branching. This annual plant is often cultivated for its first season, when it produces the most biomass. Pinch back the tips in summer for a denser, more balanced shape.
Diseases and pests
Annual artemisia is generally quite resistant to diseases if drainage conditions are respected. Monitor for excess moisture, which can promote root or fungal rot. Aphids and spider mites occasionally visit it, but cause no major damage under optimal conditions.
Fertilization
This vigorous herbaceous plant requires no regular fertilizer. Soil enriched with humus at planting time is generally sufficient. If growth slows, a moderate application of balanced fertilizer in spring can be beneficial, but be cautious not to stimulate excessive growth.
Did you know?
Annual artemisia gained remarkable scientific recognition: Chinese scientist Tu Youyou received the Nobel Prize in Physiology or Medicine in 2015 for isolating an active compound from this plant. Used for millennia in Asian traditional medicine, it has become one of the most studied plants in contemporary research for its potential properties.
Where to buy it
Plant in spring or early autumn, avoiding spells of intense heat. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, April, May, September.
Add this plant to my garden →Plants from the same family
- SunflowerHelianthus annuus
- YarrowAchillea millefolium
- Ox-eye daisyLeucanthemum vulgare
- SneezewortAchillea ptarmica
- Canadian goldenrodSolidago canadensis
- WormwoodArtemisia absinthium
Tips generated and checked by Viridia — adapt them to your local climate.