Perennial ryegrass (Lolium perenne) is a cool-season grass commonly used for lawns, pastures, and turf due to its rapid growth and resilience. It belongs to the Poaceae family and is a well-known source of seasonal allergens. During its pollination period—typically late spring to early summer—it releases airborne pollen that can trigger allergic reactions such as hay fever and asthma in sensitive individuals. The allergenic potential of perennial ryegrass makes it a significant component in inhalant allergy testing panels.
It can cause seasonal allergic rhinitis (hay fever), including symptoms such as sneezing, nasal congestion, itchy eyes, and, in some cases, breathing difficulties or asthma.
Its pollination usually takes place from late spring to early summer, although the timing can vary depending on the local climate.
Yes, it contains similar allergenic proteins to other members of the grass family, so individuals sensitive to one type of grass may also react to others.