Winter Grass

Poa annua

Grassy Weed


Poa is a low growing tufted annual weed grass with a light green-yellow colour. Both sides of the leaf blade are smooth with two clear lines on each side of the mid rib. Leaf tips may be keeled or boat shaped. Vernation is folded and ligules are membranous. Poa forms dense fibrous root. Seed heads are clustered and green to whitish.

Life Cycle

Poa is an annual that germinates in autumn when soil temperatures fall below 21°C for consecutive days and when there is adequate moisture and light. Perennial biotypes have been observed and are associated with a darker colour and more prostrate growth. Poa can form significant seed banks with the potential to produce up to 2,577 viable seeds per square metre in the upper layers of soil.