Across agricultural areas of the Prairie Pothole Region (PPR), foral resources are primarily found on public grasslands, roadsides, and private grasslands used as pasture or enrolled in federal conservation programs. Little research has characterized the availability of fowers across the region or identified the primary stakeholders managing lands supporting pollinators. We explored spatial and temporal variability in fower abundance and richness across multiple grassland categories (i.e. general grassland, conservation grassland, and engineered pollinator habitat) in the PPR from 2015 to 2018 and used these data to estimate the number of fowering stems present across the region on private and public land holdings. Both flowering plant abundance and richness were greatest on engineered pollinator habitat, but this land category encompassed<0.01% of the total grassland area in the PPR. There was a steady decrease in fower abundance over the growing season across all land categories. We detected considerable variation in fower abundance and richness across grassland categories, indicating that not all-natural or semi-natural covers provide similar value to pollinators. At a landscape scale, large landholdings such as privately owned grasslands and Conservation Reserve Program lands contributed the greatest number of fowers by an order of magnitude, though these lands collectively did not support the greatest abundance of flowers per unit area. Our research depicts spatial and temporal variation in pollinator resources across the region. Further, our research will assist managers and policymakers in understanding the role of public and private lands and conservation programs in supporting pollinators.