First, trees or tree debris has nothing to do with soil pH - that is a thoroughly debunked garden myth :-) Soil pH is due primarily to the underlying mineral content and to a lesser extent, rainfall totals and repeated, heavy fertilization. The cedars are growing there because they like that soil pH, not because they contribute to it.

Like the vast majority of plants, peonies will prefer a sightly acidic soil but they are adaptable so some minor deviation in either direction is fine. Otherwise, full sun in well draining, fertile soil and well away from larger trees or shrubs. They are listed as being deer resistant, but IME, deer don't read the books and will sample just about anything. In my garden they love any flowers or flower buds althogh they may leave the rest of the plant alone.

Be sure not to plant too deeply. That, and too much shade, are the most common reasons peonies fail to bloom.

I haven't had the deer nibble on my peonies so far, but as gardengal says, they don't seem to read very much and may take after yours. Peonies love and need full sun, like all day sun; they will survive in shade but probably won't bloom. If yours bloomed in the pot, plant it at the same level - the pips should be just below the soil level.

Full sun, deep fertile soil like in a vegetable plot. And wire support hoops in place before the shoots reach full development, the flower buds open each year. Otherwise the weight of the fully expanded blooms often pulls the stems over.

We've got numerous peonies in our garden and a large deer population to contend with. There are very few plants I'd say are "deer resistant," but peony is one of them. I've never seen the foliage touched by deer.

Peonies are one of the easiest plants for me to grow. I've got tree peonies, herbaceous peonies, and hybrids -- they all seem to do well in my acid sand. I've even got some growing in shadier sites that do okay.

As a side note, I've shifted to the Itoh hybrids. The flowers are spectacular and the stems a bit more stout. They're not cheap, but once you see 'Bartzella' in flower you'll want to have one.

Peonies are highly deer resistant--I've never had one touched-- but follow the advice to plant properly. The growth buds need to be only an inch below the surface. Any deeper the plant will live but will never bloom.