Common in the southern islands but missing from Harris and Lewis. The flight period is from August to September. Despite its name, it’s a grassland species, which also frequents gardens. The larval food-plants are tough grasses.

References: 
Leverton, R. & Cubitt, M. (2024). The Larger Moths of Scotland.
Waring, P. & Townsend, M. (2018 third edition). Field Guide to the Moths of Great Britain and Ireland.