Hierochloe odorata. SWEET GRASS

Sweet Grass, Vanilla Grass Poaceae

Hierochloe odorata, commonly known as Sweet Grass, Holy Grass or Vanilla Grass, is a wonderfully aromatic, creeping perennial grass whose freshly cut or dried leaves release the unmistakable scent of vanilla, produced by the coumarin they contain. It forms spreading colonies of narrow, bright-green leaves, with flowering stems rising above in summer. A plant with considerably more cultural baggage than its modest appearance might suggest.

Sweet Grass has an extraordinary ethnobotanical history. Among numerous Indigenous peoples of North America it is regarded as a sacred plant: its long leaves are traditionally braided, dried and burned as incense or used in purification and ceremonial practices. Braids have also been used in hair adornment and stored with clothing to impart their fragrance, while the leaves have been woven into baskets and other crafts. 

In northern Scandinavia, particularly among Sámi communities, H. odorata has traditionally been braided and used as perfume, household fragrance and for storing with clothes. Historically it has also been used medicinally as a tea or infusion for coughs, sore throats and other ailments. 

There is a genuine edible and culinary tradition too. The aromatic leaves have been used to flavour drinks and foods, including tea, pastries and salted herring, while the coumarin-rich foliage is famously associated with Żubrówka, the Polish bison-grass vodka. The small seeds are technically edible, although hardly a practical crop. 

A lovely grass for a damp meadow, pond margin or naturalistic planting, particularly where its fragrance can be appreciated after rain or when the foliage is brushed.

Height: 30–60 cm
Spread: 30–60 cm, spreading by rhizomes
Flowering: June–August
Hardiness: H6, approximately −20 to −15°C
Position: Sun or partial shade
Soil: Moist to wet, humus-rich soil
Uses: Aromatic, edible flavouring, ethnobotanical, weaving and naturalistic planting