If it's an area which gets decent water you can cheat and slip in a few canna roots, otherwise later lily varieties, eucomis might be hardy, later daylilies, rudbeckias, lobelia cardinalis, hardy hibiscus, perennial sunflowers, chrysanthemum, asters colchicum... there are bunches of late summer perennials.

I have a local nursery which is the kind of place which keeps their stock growing all season (they actually water and fertilize... not just dumpster it after it dries out once to often), so I like to force myself to visit every other week or so and buy something in flower each visit. It's a grueling schedule to keep up, but I end up with odd planting which flower all year rather than a garden bought in May and finished flowering by July.... which is not what I'm saying you did, but it's much more fun to plant shop in May rather than sweat it out in August.

Consider phyostegia, sedum spectabile and vernonia to fill the gap between summer's echinacea & rudbeckia and fall's asters & mums.

"I like to force myself to visit every other week or so and buy something in flower each visit. It's a grueling schedule to keep up"

That's the same way I do it- every Friday morning. They have the weekend stuff out by then but the weekenders haven't wiped it out yet.

OK, going through last year's photos, my Aug/Sept bloomers included asters, rudbekia, gaura, coreopsis, echinacea, hardy hibiscus, beautyberry, gallardia, Baby Joe eupatorium, Montauk daisies, hardy geraniums, a few reblooming Iris, miscanthus, cotton, the odd clematis, cimcifuga, and 'Clara Curtis' chrysanthemum

The dwarf crape myrtle and hydrangea paniculata were finishing but still looked good.

And finally - I use whiskey barrels and pots of sunpatiens and coleus to fill empty spots as they happen. I move them around to keep the color coming as long as possible and by September they are blooming like crazy.

Below pictured is October 14th and the sunpatiens are still working and will until the first freeze.

august being a dead period.. has nothing to do with climate change ... period ...

it always has been. and it will always be so ...

besides.. in my MI.. who the heck is out in their garden in august.. when it 90 to 100 degrees .. crikey.. even the plants dont like that kind of heat ...

its a good time to build some beds for fall planting.. or for the following spring ... in other words.. start getting rid of all the carp that isnt blooming to your liking.. and go look for better stuff ... and dont blame it on politics ...

ken

and all sorts of Asters, not sure which are ok for your area, but many garden Asters have wild ancestors from the prairie

Boltonia is a nice fall bloomer.

Toad Lily, a/k/a Tricyrtis. Many of them do not flower until September, into October.

Taipei Silk.

I'm zone 6 and most of my perennials are done blooming in August. Always have. There are a few stragglers but i can't think of any perennials that i grow that bloom all summer for me. That is why I work in annuals seeds inbetween my perennials in May . Easy to grow zinnias, marigolds, and cosmos. They start blooming mid summer and last until frost. I then collect the seeds for the following summer.

Hibiscus moscheutos, and Hibiscus syriacus (Rose of Sharon), come to mind first.

It's hotter than he// here in late summer, hottest time of the year.

One of our last blooming plants is Monkshood (Aconitum). Really more like Sept for us. easy to grow. A friend recommended it after I told them that slugs decimated every Delphinium I'd ever planted. Their are both regular and climbing varieties.

Hisbiscus moscheutos, Joe Pye, ironweed, Japanese anemones are the first ones that pop into my mind.

Given that I don't know your location, I don't know whether my recommendations would work for you. But my Colorado pollinator garden goes crazy in August with agastache, orange carpet hummingbird mint, plumbago, and coneflowers, complemented by Tiger Eyes sumac, Angelina sedum, blue Avena grass, and Color Guard yucca.

Thanks for so many suggestions! Will look into some new varieites.

Ken...sounds like I hit a nerve on the climate change reference. Sorry! Can't speak for anyone else, but I'm a firm believer. Has nothing to do with politics (though, since you mention it - it IS unfortunatlely a political issue relative to energy consumption, etc.)

Used to be that the perennials (and the weeds!) seemed to come up later and subsequently lasted longer into the summer season. Just the other year I mowed the yard yet in December and put Christmas lights up the next day! Crazy.

I'm often out in the garden when it's hot - not that I enjoy it, but the weeds don't stop growing just because the temps climb into the 90s. But, thanks so much for chiming in with your thoughts. I have tried lots of different perennials over the years, many of which unfortunately didn't last - so I tended to increase the beds all around the house with those that work. Many have a short blooming season - just the way it is.

Asters were suggested...used to have some but they gradually died out - so I will surely pursue planting more. Always enjoyed them in fall. Boltonia sounds interesting - I see that these are 'false asters'. I recently started using a new garden center, so will check out the perennial section in a few weeks and perhaps get some of their advice also. Japanese Anemones too. Hadn't thought of them.

"I'm zone 6 and most of my perennials are done blooming in August. Always have. There are a few stragglers but i can't think of any perennials that i grow that bloom all summer for me."

Do you water? Mine would stall out as well if I didn't spend most of August with a water hose in one hand and a cold drink in the other. Those lawn chairs scattered around my back yard are where they are for a reason, lol.

cearbhaill (zone 6b Eastern Kentucky), No, I don't water. Mother Nature is generous in that dept. The only thing I do water is my planters/baskets if it hasn't rained for a couple days , brand new plantings or veg garden sometimes. Majority of people don't water lawns or have any irrigation systems. I don't have a large variety of perennials. I like the deer resistant, dig a hole, throw them in, and they will grow type. Daylilies , hostas, peonies, daises, clematis, iris, spiderwort, etc FYI ya I know deer love hostas, but they don't bother them if they are planted around the house foundation.

New England aster, New York aster, smooth blue aster, wood asters (many aster cultivars available), Helenium, Rudbeckia fulgida, Lespedeza violacea, flax leaved aster aka stiff aster, sweet goldenrod, showy goldenrod, Rudbeckia laciniata and Agastache scrophulariifolia still blooming, Lobelia siphilitica, Liatris scariosa, Chrysopsis mariana, Joe Pye weed, various Iron weed species (some really nice ironweed cultivars out now), Perennial sunflowers, hyssop leaved thoroughwort, gentians, ladies tresses orchids, pearly everlasting. There are a ton of north american plants flowering in the late summer, think any warm season plants from around the world.

globe thistle

Aster with roses and cosmos in the background

Mums with Pennisetum

I forgot , Hibiscus - I've been very happy with this one.... 'Berry Awesome'

Glad to hear from someone with real-world experience with Berry Awesome. It looks fantastic in photos.

I've had a couple of named varieties of Hibiscus and this one is my favorite.

Phlox Jeana. Blooms mid summer to fall. It was the top rated Phlox in Mt. Cuba s trials. Its a Swallowtail butterfly magnet.

sounds like I hit a nerve on the climate change reference. Sorry! Can't speak for anyone else, but I'm a firm believer.

You can speak for me.