Vanilla Sweet Grass (Hierochloe odorata or Anthoxanthum hirtum) is a cool-season grass known for its aromatic, vanilla-scented foliage. It is sometimes used in herbal medicines or beverages, and is burned in indiginous ceremonies to attract good spirits. This petite native grass sports glossy, green foliage and attractive blooms that last through the summer. Sweet Grass spreads by underground rhizomes, up to 2 feet per year. Due to this spread, it can be difficult to control and eradicate if it spreads to an unwanted area. Keep this in mind when choosing a planting area, or restrict this growth by placing in containers situated in an area where its wonderful scent can be enjoyed.