Not only full blazing MO sun, but there will be reflected heat off the house. Pretty tough. How far away from the house can you plant? Any chance of a pic of the area?

tj

Yeah, I would provide Smooth Hydrangeas with afternoon shade in almost all places but paniculatas -including compact ones- can handle more sun. But no hydrangea will tolerate long dry spells and these will trigger browning of leaves or worse. Short dry spells can make the plants abort development of flower buds or abort opening of existing flower buds; depends on exactly what did you mean by "dry spells" and at what time of the year. If you want to experiment with the summer sun in that location, get only one smooth hydrangea and grow it in a pot so you can easily move it elsewhere if it does not handle the summer well in that spot; but get something that will provide some water regularly.

No H. arborescens will look good in full sun in that location. It's a plant with large leaves that readily lose moisture in sun, so they will be at best limp every afternoon, and most likely crispy leaves and browned flowers if the buds don't abort since the roots can't keep up with the moisture lost through the leaves in hot settings. Stressed H. arborescens are ugly. I have seen reference to folks living in cooler, more northern settings who have managed to keep them in good shape in full sun, but even that is the exception. Mine do well in morning sun from 9 until about 1 or 2 pm, but then they are in bright shade from the house the rest of the day. I am also considerably cooler than you are.

The most sun tolerant hydrangea species is H. paniculata. Mine grow in all day sun (though not against a building) in a bed that is well mulched but doesn't get watered, though I did water it during periods without rain when the plants were settling in during their first couple of seasons. In your case, as Luis suggested I would start with one H. paniculata to see how it does in that setting, mulch well with something like shreddd bark, and pay close attention to its watering needs. They are available in a range of ultimate size from about 3' to 12' or larger, so you should be able to find one that suits your size needs. Blossom shape, size, and color intensity will vary some also. If it does well, then add others. Alternatively, go ahead and get a whole set of them, but choose an alternate site that is less severe so that if they don't do well in front of the house you can move them to that second choice spot and enjoy them there.

Thanks for the comments and guidance. I'll research the H. paniculata, and give it a go. Very helpful!

Looks like H. paniculata 'Jane', also referred to as little lime is what I'll be going with! It's not on my native plant palette, but I love Hydrangeas and that's enough reason for me to put some in the ground.

Good luck and monitor the soil moisture, especially in the summer months.