If you're not already planning your garden for Spring time, it's never too late to plan for future seasons. The truth is that many perennials won't flower the first season anyways, but they are a massive investment for future seasons. If you choose perennials hardy for your region, they'll winter over for many years to come, they'll be bigger every season, and soon your efforts will be reduced each year while the perennials simply do their thing. The two biggest differences between Annuals and Perennials is that Annuals flower pretty much non-stop throughout one entire planting season, and die at the end of that season, while Perennials have a limited flowering time, usually between 4 and 8 weeks, but will winter over and produce a larger plant each year to follow. If you have a longer season in warmer climates, you may get a second bloom out of some perennials.
Here's something you may want to explore this year. If you have a good selection of perennials throughout your garden, then observe which perennials get the most attention. Whichever ones outperform all the rest, plant a heavy dose of them for future years. It's nice to have selection, but not all flowers are preferred. It's extremely difficult for me to know which perennials outperform in each climate because I really am limited in my much colder climate. So ask around, observe and plan to go much heavier on their favorites. One tip I can give about plant choice is to choose taller varieties. Hummingbirds become quite wary with flowers near the ground, so pick those 18 inches and taller if you can. Of course this doesn't really apply to Annuals, because you can plant them in planter pots and hang them well above the ground to keep the feeding hummingbirds away from predators that lurk below.
Here's one of my favorites. Delphiniums can grow from 3 ft to 8 ft in height, with a wide range of colors, generally in the Blue/Purple spectrum. They are very hardy in colder climates, and like a mixture of sun and shade. If their roots are wet, you'll get a lot more height out of them.
I have hundreds of Delphiniums around our garden, and they attract hummingbirds like no other, especially at the time when young hummers are leaving the nest. This may not be a choice that does well in your region, but if you have a perennial that outperforms the rest, lose control with them. Give hummingbirds far more reasons to return or stick around.
Ruby-throat hummingbird, N.E. of Edmonton, Alberta, Canada. Aug. 5, 2019.