If they have gone to seed, I can only assume you didn't deadhead them promptly as each flower deteriorated. (Deadheading means removing blooms that are past their prime and declining.) If you don't deadhead, the flowers go to seed. Since the purpose of the plants is to form seed, as far as the plants are concerned, they've done their job...they have set seed and have more or less guaranteed they'll perpetuate themselves via the seed, so they can relax and cease blooming.

If you still have green foliage, remove the dead flowerstalks, water well, and hope for reblooming on at least some of them.

Delphiniums struggle in the heat here, so that one may or my not come back, but it really isn't a full sun plant in Oklahoma's heat/intense sunlight.

In the years I've grown scabiosa, it did bloom all spring, summer and into fall as long as I kept it deadheaded and well-watered. I did have it in full sun.

I don't grow gaillardia in my garden because the native one grows in the pasture. I don't know how the hybrid gaillardias perform, but the native ones generally bloom in May and June and then go to seed. However, no one is deadheading them in the pastures or alongside the roadways, so they might perform differently if they were deadheaded.

My achilleas bloom all summer if deadheaded promptly as the flowerheads begin to brown. They are in full sun.

Shasta daisies bloom in spring for me and I had them for 7 or 8 years before they died in last year's drought. Sometimes they rebloomed and sometimes they didn't, but they never died as long as I deadheaded them and kept them well-watered.

Black-eyed Susans are long-season bloomers as long as you keep them well-watered. They will benefit from being deadheaded too. Mine often bloom from about May through August.

Watering every other day might not be idea. Such frequent watering encourages shallow roots, and shallow roots often can't take the heat and then the plants die. A lot depends on your soil. If it is very fast-draining, like pure sandy (not sandy loam) soil, they might need watered that often. Sandy loam or clay shouldn't need every-other-day watering though. Do you ever check or feel the soil to see if it is moist or dry, or do you just water by timer no matter what?

Hollyhocks bloom for me most years from late-April thru early to mid-June. I still have a couple in bloom now. You need to deadhead them as well. I take Fiskars garden scissors and snip off the dead blossoms before they set seed and that keeps them in bloom longer.

So, I'm assuming you either didn't deadhead at all or you deadheaded too late. And I'm assuming your plants have some green left on them and didn't die back completely to the ground. I'm more concerned about the issue of watering every other day. I'm in an area that is very hot and dry and I only water my flowers once or twice a week if no rain is falling, and not at all in the weeks that rain is falling. And, by the way, I am in a part of Oklahoma that is very hot and dry. In my experience, frequent shallow water just gives you plants that have to be watered more often and struggle more often. Consider watering less often but for longer periods so the water goes more deeply which will encourage the plant roots to go more deeply as well.

If you're looking for ideas about which perennials are long blooming in Oklahoma, here's what we have going in southcentral OK, where most of these have been in bloom since May. Currently in bloom in our garden at the present time are: tall verbena (verbena bonariensis), salvia farinacea, daturas, Malva sylvestris 'Zebrina', Malva sylvestris 'Mystic Merlin', Four o'clocks, Texas hummingbird sage (either is perennial or a reseeding annual depending on the winter weather here),cannas, achillea 'Summer Pastels' and achillea 'Summer Berries', Butterfly Weed (both orange and yellow ones), Hollyhocks (single flowered types), swamp mallow, hardy hibiscus and Veronica. All of these are in full sun or get a little shade very late in the day....maybe from 4 or 5 p.m. on. Most of them will bloom well into fall, and some of them will bloom until frost.

Hope this helps.

Dawn

Dawn,

Thanks so much for taking the time to respond and for the great advice. I will start dead-heading pronto and see if I can get another rebloom. They all got so big that I didn't think it was possible to go in and prune. There's plenty of green still on the plants so I think there's still some hope.

As for the watering, we have very sandy soil. When we moved into the neighborhood, everyone told me that you have to water short periods every day around here because the soil is so sandy. It certainly makes it easy to dig and plant... but there's little moisture-holding to it. I only turn on the irrigation system to run every other day when we're backing in the high 90s and 100s without any rain. I've got a big compost pile going so I hope I can start amending the soil, little by little each year.

I'll look up all of the plants you mentioned and see which to try next year. I'm so grateful for your list of recommendations! My take away lesson from this year is that the black-eyed susan are a winner for me. I'll probably plant more of those next year.

Allan: If your soil is sandy, I would incorporate compost, it will help hold water in your soil. Also, some kind of mulch will help shade the soil.

I do a lot of flowers. I really don't expect any of my perennials to give me more than a couple weeks of bloom, so I use a lot of different types. If you want constant bloom, annuals are really the way to go. I love zinnias for late summer bloom. They are easy and they will take the searing heat we get.

I love black eyed susans, they do give wonderful bloom. Becky Daisies will give you a strong white bloom. I found scabiosas, especially the perennials, to be rather short lived. I do have one that has come back for four or five years, but the rest of them have long disappeared. The annual scabiosas will actually act as a short lived perennial for me as well.

Did your delphs survive? I have never had very good luck with those, I've given up on them and use the annual larkspur instead. I saw some GORGEOUS delphs when I was in Wisconsin last week. Northern gardens make me drool. :)

I'm attaching a link to my photobucket site. The main part is mostly single shots, but the "yard shots" album will give you a little more panoramic view.

Lisa

Mulch, mulch, mulch!

Aside from that, you might collect the seed heads as you deadhead, especially those that are nicely dried. Then you can give them away to friends, or plant them in other locations next year.

I like zinnias. I have a bunch of them blooming in my front yard right now and they are attracting a lot of butterflies.

"Northern gardens make me drool" Hah! I had a northern garden in St. Paul and I can tell you - they're pretty for such a very short period. Then the rest of the year they're frozen solid!