Vegetative Growth
Flowering Plant

Sweet Vernal Grass


(Anthoxanthum odoratum)

An early flowering grass, strongly scented with coumarin, when cut as part of a hay crop it is this plant that gives hay its sweet smell. It is an adaptable plant, found growing in a wide range of habitats, with a high stem to leaf ratio.


It may be added in small quantities to mixtures designed to produce sweet, soft, traditional meadow hay.


A perennial species, its early flowering allows it to go to seed early in the season which helps it to continue regenerating from seed, which may aid the persistence or spread of plants.


Sweet vernal grass is one of the earliest grasses in the spring and will grow on most soils. The coumarin content adds to the sweet smell of meadow hay.

Frost Tolerance

Reasonable frost tolerance.

Sowing Rate Advice

8kg per acre / 20kg per ha

Not normally sown as a pure stand.

Mixture Sowing Rate Advice

0.2 - 0.5kgs per acre / 0.5 - 1.25kgs per ha.

An expensive seed, so used in small proportions in mixtures.

Ideal Sowing Time

Sowing this expensive seed into warm soils with adequate moisture will give it the most reliable germination and establishment May to August.

Distinguishing characteristics


This is an oval to rounded shaped seed. It varies in colour from dark grey to brown, an awn or whiskery tail maybe visible. It is a small seed measuring 2mm in length. Due to the small and light size of the seed, it may be coated in a clay coating to make it easier to pack and sow.

Vegetative State

Flowering Plant

Flowering Plant
Leaves are green and finely pointed The ligule is long, up to 5 mm and membranous, it is notably hairy. The panicle is spike like and dense, with an ovate to oblong shape. It can reach between 1-12 cm with a greenish to purple colour. The compact panicle is sweet smelling, with glumes that contain the fragrant oil Coumarin, giving a pleasing smell to hay crops. It can reach heights varying from 10 - 80cm. The root system is composed of thin white fibres

Additional Info

Flowers Mid April Onwards Average seeds per kg - 2,500,000 per kg

Works well with

It can be sown in mixtures designed to produce a traditional meadow hay sample, such as Timothy and meadow fescue. Due to its non aggressive nature it can also form a component of wild flower mixtures.

You can find Sweet Vernal Grass in the following mixtures