chalyse said:Becky, I am in the same 100-degrees+ summer as you and I try to grow mine with some kind of shade to shelter them from "too much" sun! Some can hide from the worst heat and sun by the side of our shed, some get a bit of help from some 5-foot shrubs, many are kept on or in the shade provided by a raised porch with lattice panels, and just as many are grown under deep shade trees.
This year I am also trying to keep up with early watering, really soaking the unprotected beds, but even now they are drying out very quickly. I know it might also help to put those water-absorbing crystals under the roots, but I really want to avoid synthetic, artificial or assistive materials in the garden soil.
Will be interested in hearing how others achieve some protection for their high-heat/sun daylilies ... in our zones, the accepted wisdom about sun-loving daylilies can leave us with melting, bleeding, wilting, bleached out flowers that stop appearing as soon as the temperatures rise. What is more distressing is to see how battered the roots and fans get after the prolonged exposures.
On the other hand, I do now rotate my "best" daylilies to the "heat furnace" section of the garden to track their performance. Slowly but surely I am finding which of my best daylilies also have some real fiber to them - and it is sometimes quite a surprise which ones really benefit a garden the most. 
I'm in the same situation with regular rains ending by early June and Temps running up to 100+ in July and August. First, getting into the habit of early and deep watering will help. One question I had which I didn't see anything about: Are you using mulch around your daylilies? The last two years I've gotten proactive at mulching my plants and they are surviving much better (still need deep watering, just not as often). The plants have stayed large and while they did end up looking kind of challenged after heavy May-early July blooming, they've picked up now in August when the temps decreased and we've had some rain. One big thing is the mulch keeps the soil much cooler than areas without it and you can tell there's more moisture (without it's like a desert!). I'm using pine nuggets, shredded pine bark and shredded hardwood (as well as some oak leaf mulch). Also, I've used 3/8-inch soaking hoses and left them dripping 2-3 days at a time for deep watering. A good hose can be run underneath the mulch for better performance.
Some of my daylilies are in direct sun (both morning/midday on east side and afternoon sun on the west). I've just taken up some Knockout roses that were in a high shade area that weren't performing (though that appears to be due to soil not being properly prepared before planting). I'll be improving the dirt and planting daylilies there. This will be the first "shady" read but fortunately it's high shade from some old oak trees about 20 feet away with the lowest branches about 25 feet up. The spot gets some morning and afternoon direct sun but mostly dappled sunshine. I plant to plant 'Dallas Star' which I understand performs well for many people with shady locations.
