Lovely blooms, everyone!!
Karen - in answer to your question in regards to the average temps in my area - average highs in the winter is around 50-55, average lows are 40 or so. We get maybe 14 days of 32 or below, with the lowest of 27 degrees. It is rare that we get more than 2 freezing nights in a row. Spring temps start in March and can get up to the 70's, but mostly 60-65 degrees. Last frost day is the mid January or so. That is just enough winter chill hours for most of my peonies to bloom. I only have 1 or 2 species out of 50 that has not bloomed. Summers can get over 100 degrees by as early as mid-May. But, with the low humidity, and the cool delta breeze in the evenings, the summers here are not bad. I turn on the AC only when I am expecting company since my house is fairly well insulated. So, as far as peonies go, it is important to plant early bloomers so that all blooming is done before the heat comes. Protection from afternoon sun is a must. Tree peonies bloom first at the end of March, herbaceous ones start second week in April, with the ITOH in between. TP Kinkaku blooms later than the early blooming herbaceous ones. All blooms are finished by mid-May.
As some of you are just starting your peony season, mines is half over. Red Charm bloomed late last week and only mid to late season ones are left.
. We can even start a new thread on peony growth in northern gardens. When our guys start blooming we may get back to this thread. 
