- Family: Mint Family – Lamiaceae (Labiatae)
- Growing form: Perennial herb.
- Height: 20–60 cm (8–24 in.). Often many-stemmed. Stem rigid, 4-edged, almost glabrous. With strong scent.
- Flower: Corolla irregular (zygomorphic), blue–purple, 20–30 mm (0.8–1.2 in.) long, clearly longer than calyx, fused, bilabiate, long-tubed. Corolla upper lip 2-lobed, narrow, convex; lower lip 3-lobed, central lobe clearly bigger than lateral lobes. Calyx bilabiate, 5-lobed, 15-veined, bluish violet. Calyx upper lip 3-lobed, central lobe clearly broader than lateral lobes. Stamens 4, of which 2 short and 2 long. Gynoecium composed of 2 fused carpels. Inflorescence spiked; a short, dense whorl.
- Leaves: Opposite, mostly stalkless. Blade linear–lanceolate, matt green, with entire, downward-curved margin,
- Fruit: 4-parted schizocarp.
- Habitat: Gardens, river banks, ridges. Ornamental, left over from old gardens.
- Flowering time: July–August.
Northern dragonhead thrives in dry meadows, moors and rocky outcrops. It is by nature a typical steppe plant – in the Nordic countries it is most likely a leftover from a drier period of history which had a more continental climate. Nowadays the species appears in small areas in south-east Norway and southern Sweden. The species doesn’t grow ferally inside Finland’s current boundaries, but the closest stand is right behind the eastern border in Ladoga, Ääninen and Aunus Karelia. It is also cultivated as an ornamental and can escape into the wild in suitable habitats even though it has no great abilities to spread. Stands in natural habitats that are found in Finland have originally been planted as ornamentals. Northern dragonhead and its close relations are very rare in the wild and usually only casual visitors. Northern dragonhead can be identified by its linear leaves that have entire margins; its close relatives have broader, serrated leaves. Additionally, dragonhead has a powerful, heady fragrance while its close relatives are almost scentless. In days gone by the fragrance of a flower was given much more emphasis and strongly scented dragonhead created its own special atmosphere.
Siberian dragonhead (D. sibiricum) that has escaped from gardens can be most easily differentiated from dragonhead by its serrated, ovate leaves.