Hybrid prairie mallow is a group of hybrids between Sidalcea malviflora and other species. 'Rosaly' is a variety I grew from seed from Jelitto. It does not come 100% true from seed, so there is some variation in flower colours, although all are some shade of light pink. It seems fairly hardy, it's been growing in my yard since 2017 and flowers every fall. It usually starts flowering around mid-August and the flowers last until winter sets in. It is unaffected by light overnight freezes. The flower stalks need staking.