Sweet Grass, known scientifically as Hierochloe odorata, is a perennial grass species recognized for its unique and intensely sweet fragrance. This plant grows naturally across the cool, temperate regions of North America and Eurasia. The distinct aroma has made it a valued material for basketry, flavoring, and perfumes for centuries. For many Indigenous peoples across the continent, sweet grass holds deep cultural and spiritual significance, often being one of four sacred medicines used in various ceremonies. Informed acquisition requires understanding the nature of this plant, from its scent to its sourcing.
The Chemistry Behind the Aroma
The sweet and warm fragrance of Hierochloe odorata is primarily attributed to coumarin, an organic compound. This chemical gives sweet grass its characteristic vanilla-like scent with notes of freshly mown hay. The compound is not readily noticeable in the grass when it is alive and green.
The release of the distinct aroma occurs when the plant cells are damaged, typically through drying, cutting, or crushing the leaves. Enzymes within the plant break down a precursor molecule, releasing the volatile coumarin compound into the air. This process is a natural defense mechanism for the plant, as coumarin can have a bitter taste to deter herbivores.
The concentration of coumarin is highest in the long, sterile leaves that appear later in the growing season. Dried and braided sweet grass material retains its powerful fragrance for many years. The enduring scent is a direct result of the chemical change that occurs as the grass is harvested and cured.
Cultivation and Ethical Sourcing Considerations
Hierochloe odorata is a cool-season grass that thrives in specific, consistently moist environments, such as wet meadows, low prairies, and along the edges of marshes. The plant propagates vigorously through an extensive network of underground stems called rhizomes. It prefers full sun to partial shade in rich, loamy soil, and it can be successfully grown across USDA hardiness zones 3 to 9.
The plant’s preferred habitat is often under threat from development and loss of wetlands, which puts pressure on wild populations. Wild harvesting, especially when done improperly by pulling the entire plant from the root, has led to a decline in sweet grass stands across its native range. This has created an ecological concern over the sustainability of commercially sold material.
Consumers should prioritize purchasing from sources that use cultivated plants or adhere to traditional harvesting methods. Traditional harvesting involves cutting the leaves above the ground, which stimulates the plant to grow more vigorously and ensures the survival of the rhizome network. Seeking cultivated material helps reduce ecological pressure on wild stands and ensures a sustainable supply.
Direct Sourcing: Where and How to Purchase
For those looking to purchase Sweet Grass, the options generally fall into two categories: live plants for cultivation or dried material for ceremonial and aromatic use. Live plants, often sold as rhizome divisions or plugs, are best acquired from specialized native plant nurseries or herb farms. These suppliers focus on propagating the grass through division, which is the most reliable method for home gardeners.
Dried material, typically sold as braids or loose bundles, is available from online retailers and specialty shops. When purchasing dried material, the most responsible choice is to seek out Indigenous-owned businesses, co-ops, or organizations. These vendors often adhere to traditional, sustainable harvesting practices that honor the plant’s cultural significance and promote its regeneration.
To ensure quality and ethical sourcing, consumers should look for clear labeling that specifies the material is either “cultivated” or “sustainably harvested.” Suppliers should be transparent about whether they are growing the grass themselves or working directly with Indigenous harvesters. Verifying the source helps ensure that the purchase supports the cultural integrity and ecological health of this unique and fragrant plant.