Sweet wormwood (Artemisia annua) is a common wild medicinal herb that can be used to extract artemisinin.

Sweet wormwood (Artemisia annua) is an annual herbaceous plant of the genus Artemisia in the Asteraceae family, and it is very common along field edges, roadsides and wasteland in most parts of the country. The whole plant carries a strong, distinctive aroma; pinch a leaf and rub it, and the smell is quite pungent, so many people have grown up treating it as an unremarkable weed.

Its stems are upright and generally grow to around one meter, with finely pinnately divided leaves, and the whole plant has a yellow-green tone. By late summer and early autumn, many tiny yellow flowers bloom at the tips of the branches, and this is exactly where the name sweet wormwood comes from. Its seeds are very small and scatter with the wind once mature, so the following year a patch can grow on its own without any tending.

Ordinary as it may look, the greatest value of sweet wormwood lies in the fact that artemisinin can be extracted from it; this is an important anti-malarial compound, and it was from this plant that Chinese scientists drew their inspiration, with the related achievements benefiting the whole world. In addition, people often use its strong scent to drive away mosquitoes, and some also store dried branches and leaves indoors.

If you want to grow sweet wormwood yourself, it is not difficult. It likes sunny, well-drained spots and is not demanding about soil; after temperatures warm up in spring, you can simply scatter the seeds, water appropriately as usual, and it is fairly drought-tolerant. One thing to note is not to confuse it with the similarly named Artemisia carvifolia; the two are different plants, with differences in flower form and scent.