I’ve traditionally used the USDA Plant Hardiness Zone to help decide what to plant and when. While it provides great information, as you probably know the zones cover a wide range of territory. Cincinnati is in zone 6A along with parts of California, for example. I’m not a scientist but I find it hard to believe that the same plants will grow successfully, while supporting local pollinators, in both Ohio and California.
In learning how to select native plants that will help the most, I’ve become focused on ecoregions in addition to plant zones.