Oakleafs require some morning sun and then shade to protect from the afternoon sun. Their roots are very sensitive to water issues and will develop root rot if allowed to stay wet for long periods of time. So try to keep the soil evenly moist (not wet) as best as you can. Also, keep them well mulched, with 3-4" of the stuff at all times.
also let me ask - I have this one in a pot and I'm moving it around to see where it is happiest... I left it in too much sun for an afternoon and now it has some brown stains on those lovely leaves. Is this sunburn or something else? I remember it having a lot of these spots last year after I bought it.
Looked at my Little Honey closer tonight. Most leaves looked great. I did find a couple of leaves with brown spots - maybe mechanical damage from falling litter or wind damage? Had one leaf rolled up - looked like a caterpillar made a cocoon or maybe some kind of spider.
Here it is this evening around 7 PM (full plant and the couple of damaged leaves)
Browned areas that originate from the edges and move inwards might suggest a soil moisture problem. A newly planted or young hydrangea will do fine if you give it 1 gallon of watering per watering and keep it mulched throughtout the year (3-4" of any organic mulch will do).
The leaf spots (brown or purple; circular) on the oakleaf are a fungal infection. Try watering the soil and never the leaves to see if that helps control the problem. In the Fall, dispose of the dried out leaves and blooms in the trash instead of the compost pile. Do not overwater or keep the soil/mulch wet as this promotes the development of these fungal infections. Also, do not plant shurbs near these so the wind can help lower the moisture levels around the plant. The problem does not appear serious enough to buy a fungicide.
Distorted new growth suggests aphids, mites or, less common, the hydrangea leaf curler insect or moisture problems on new growth. Aphids can be controlled with beneficial insects or insecticides like Bonide's Eight. Mites can be controlled with a high-energy water blast to dislodge the pests. Insecticidal soap/spray can also help. You can also release lacewing larvae, parasitic wasps and ladybugs to control an infestation.