Dear All; Thanks to all from bringing up details, I intentionally skipped. Simply could not be all inclusive in an already 'too long' intro to the topic. To mention a few: John I. Intersectional peonies are hybrids between herbaceous and woody species. Previously thought impossible, this was first accomplished over 50 years ago by a Mr. Ito (Itoh) in Japan, but far surpassed by modern hybrids including a wide variety of species on both sides of the cross. Modern hybrid especially those by Roger Anderson of S. Wisconsin are incredible plants. Intersectional hybrids (IS) have the foliage and flowers of Tree Peonies with the habit of herbaceous peonies: deciduousness. This means the best have silky flowers of the rich lutea TP hybrids (yellow, salmon, peach etc.) but the added hardiness of P lactiflora. Most of these are very vigorous. I predict these will be even more popular as the price comes down. Right now one of the top IS peonies ,'Bartzella' is usually about $250. ! More exciting down the line too! Saunder and Daphnis TP hybrids are generally from P. lutea breeding and should do fine in milder climates. I'd give them protection from sun and a pH above 7. P. ostii is usually available (and low priced) as 'Fen Dan Bai' or 'Pheonix White'. It is grown in huge quantities for the medicinal root market in China. Most plants, regardless of name, are hybrids, but flowers are close to typical. P. rockii might not do as well in your milder climate although it is fine in Central England. This is usually more expensive, but prices are coming down as more plants come from China. Lots of selections too.Over 200 named forms! Al Roger's paperback has been available for a month or so. Printing was done quickly. GL Osti's book on Tree peonies is out of print and demanding a triple list-price on the used book market. Jane Mc. You are absolutely correct about my bias in the intro toward southern west coast. My intent is to intrigue more people into growing mild climate peonies. Some of the best herbaceous and tree peonies grown in the US come from the Pacific NW. There are many growers who have formed a semi-professional group, the Pacific Northwest Peony Society. Some of the better known retail mail order growers are Caprice Farm Nursery, Adelman peonies, Pacific peonies and many others. P. brownii is quite hardy. I grow it here, but it demands excellent drainage and full sun anywhere. Yes Josef Halda grows it in the Czech republic too, but it is more demanding for most people outside its natural area, than it is worth as a garden plant. A challenge, but why? P. lutea var/ ssp ludlowii or P. ludlowii as these variants suggest is a name with some controversy. It is one of the largest and most vigorous of the TP species getting to 12 feet and possibly more. Larger in all respects to typical P. lutea it comes true from seed. It is popular and widely grown, but not 'reliable' farther northern that a wet Zone 6. John I also comments on understocks "are well known to be able to produce random eyes on the roots if they are removed from the mother crown" Yes and no. Again very species specific and the best grafters select species, even cvs. that DO NOT produce adventitious buds or shoots. Buyers should inquire if plants for sale have begun to produce their own roots or not. Some, like Rick Rogers sell grafted plants, but ONLY after they have acquired their own roots and the under-stock is removed. Cheap grafts are usually new grafts without their own roots. the old 'Buyers Beware'.. As for Jim Mc, Some cv do indeed produce so vigorously from adventitious buds on 'blind' roots that they are propagated by this method. The selections and hybrids from P. peregrina are notorious. The cvs 'Coral Charm' and 'Ludovica' (a recent APS Gold Medal winner) can be pests because it is so difficult to dig up the whole plant without leaving a scrap of root even 12 or 18 inches deep. This will produce buds and return in a year or two with complete vigor. I'll respond to other comments, but do want to ease Roger's mind about P corsica (previously known as P cambessdessii). I mentioned this in the Intro Part 2 and think it is the mostly widely grown of the Mediteranean group ( excluding P. mascula which extends beyond this area) and much loved in mild climates. It is probably hardy in more northern reaches with better drainage and some protection from intense mid-summer sun. Growing some of the species, especially when relatively far from 'ideal' environs, may mean some creative gardening. For example, here, tree peonies do very well on the north side of the house where they get almost no sun except briefly in the height of summer. TP in sun often get burned edges to leaves. Takes some fore thought and planning. More later. Jim W. -- Dr. James W. Waddick 8871 NW Brostrom Rd. Kansas City Missouri 64152-2711 USA Ph. 816-746-1949 E-fax 419-781-8594 Zone 5 Record low -23F Summer 100F +