The problem with a lot of commercial bee houses is that the manufacturers often use stems with aperatures far too large for native bees and wasps. The good part is that you can often rip out the unused sizes and replace them with better sizes.
Always looking for interesting plants for pollinators and food! Bonus points for highly, and pleasantly scented plants.
"Si hortum in bibliotheca habes, nihil deerit." [“If you have a garden and a library, you have everything you need.”] -- Marcus Tullius Cicero in Ad Familiares IX, 4, to Varro. 46 BCE