How about a beach umbrella? Just kidding!
I don't think it's going to like a lot of late sun but keeping it well watered will help. If you really wanted to baby it a light misting on hot afternoons will make it happy but I'm too lazy for that. You should be prepared for it to sulk on hot days. It should perk up when it cools off at night. You didn't say how big it is. If it were me I would try to plant some fast growing tall plants on the south side to block the hot afternoon sun. Or a couple of obelisks maybe with clematis? Extra water will be the key. Hope you don't get drought restrictions. -Ais.

Gecko - Yeah, I had actually already considered the beach umbrella option. ;)

Actually, I think what I might do is put a potted plant in that space that can take the full sun and provide some dappled shade for the little hydrangea (which is about 4' wide, btw). I was thinking of the clumping bamboo for that, or maybe even a tomato plant since I could hook into the drip system that's covering the hydrangea. A potted plant would be good because I could move it in the off season and not have to look at a permanent structure like a trellis or a lattice wall.

It's still small, would a flower bed work to shade it? If so, you could plant Sunflowers or Castor Beans to shade it just for the Summer, while you think it over. It's not too late to consider moving it to a shady area, since it's still small. I grow Hydrangea and they are one of my most favorite shrubs/perennials. Email me to discuss if you would like to. Robin in NC

Hey Robin - Good tip on the Sunflowers, that's another I hadn't considered.

I'd really rather not move it, but if it just doesn't work in this spot, I'll consider that in the dormant season for sure.

FWIW, I really recommend the Endless Summer variety. Blooms on new and old wood all season.

I was thinking a couple of bananas would give some nice filtered shade...just an idea.

I think bmaxx's idea of a couple of bananas, in or out of pots, would be an ideal solution. I was thinking the same thing. I have two potted bananas, a large one, and a medium-sized pup that I am going to put on the south side, and on the west side, respectively, to shade mine.

Do you guys bring your banana plants indoors in winter?

Could you put in a small tree to help w/the dappled shade? I'm thinking maybe a dogwood? Or even a little redbud if you could keep it pruned so it doesn't overtake anything.

JW - I think a small tree is a good long term solution, maybe one that I'll pursue in the late fall dormant season. For now, I'm just trying to figure out something to get it through the hot summer.

Would a dogwood handle a full sun location like that?

FWIW, I asked about a banana plant while at a local nursery yesterday. All they had were the dwarf bananas, not good for my purpose, but this was a pretty small nursery. Are banana plants fairly common at nurseries, and at this time of year?

I live in Charleston, and have seen dogwoods out in full sun here; I think as long as they got enough water, they'd be okay. I think even the dwarf bananas get up to around 6-8 feet tall. Where do you live? Park Seed and Wayside Gardens, in ummm - Greenwood? upstate SC has them, I think.

Dwarf bananas get to 6-8 feet? In one growing season?

Heck, that's all I'd need for this space. How tall do regular bananas get...15-20 feet?

As for the dogwoods, I actually think they're probably okay if they have a chance to grow up in a full sun location (with ample water as you said). It's when they've lived their whole life in a high-shade area, then get transplanted to full-sun, it can get dicey for them.

I planted Pink Velutina Bananas last year, left them in the ground, and they are back up already.

The Musa Basjoo, that is supposed to be hardy here, has not come back yet.

I'm sure the hydrangeas would love the bananas for shade, both love lots of water and feeding. They do have a terrible ugly spell in the fall after freezing though. But they are SOO pretty that I find it is a good trade-off.