in my zone 5 .... always that qualifier with the world wide audience .... and it would be no different for z6 ... or 4 ... September still has those 80 degree days available .... not good ... if you get 7 in a row .... October has cool days... 60 to 70F .... and cold nights ... and heavy dews .... NO EVAPORATION of ambient water .... and that is the key ... IMHO .... dig.. move.. water.. and you MIGHT not have to water it again until next spring .... leaves are dormant ... no big pull for the truncated roots to water the leaves.. plus all the water in the air... its like a greenhouse without the house .... PLUS... two cool seasons.. this fall and next spring.. to grow roots.. until the heat hits late next may or so .... that should be enough reasons to remember Oct .... lol carpe shovelum.. now.. go do the right thing.. and move them at will .... you know.. you can do this any time of the year, with a little care ... the issue is stacking the odds in your favor .... in case you forget to tend one way out back.. odds are it will survive without you ... and i fully understand the stresses on your worrying .... been there.. done that.. had some failures... succeeded wildy ... just do it.. and write the failures off to fate... ken

thank you all for the suggestions... When the Endless Summer craze hit a few years back, I got rid of quite a few Nikkos, thinking I would have constant bloom from ES's. I cant even get one good flush of blooms on the ES's... I've tried them in sun, part sun, shade, etc. and its basically hit and miss... some years are decent and some years nothing.. I see some beautiful, big old 5ft Nikkos (I'm presuming) around town that bloom year after year on very sturdy, upright, bushy plants. The ES's seem to be somewhat weak, "leggy" growers, often just flopping over, and not getting much larger than 3ft tall. I missed my Nikkos so much that when I stumbled upon a few- by pure luck- I bought 3 nice ones in 7 gallons. I was shocked to find them in Cleveland. I thought I would experiment w/ a few various remontant or very cold hardy cultivars and see if there was much variance between them, but I've heard that there isnt much-- just thought I would check w/ the experts on the forum here. I also saw some ASB's at the same place I found the Nikkos so, I guess I will try them as well.. Hardiness doesnt seem to be an issue, I usually mulch w/a bit of leaf compost, but I cant recall significant dieback this close to Lake Erie. I would love to find a very deep blue like the Enziadom, or some of the other older "standbys" but the problem is locating them, in that every nursery is saturated with Endless Summer. Anyone know a source for Enziandom?

I have three asb's that bloom well for me here with winter protection.Your plant will survive here but to have blooms it will have to be covered in the winter. That's a little extra work and still a little iffy because of late frosts that could kill the new buds. Endless Summer is the one I would recomend for zone 4.

H. quercifolia is somewhat challenging plant for z5. The most of the problems will occur in a first few years. Once established it will be relatively trouble free plant, though not a reliable bloomer. After all it's a z7-8 (NC, GA) native plant. First, it need 2-3 years in ground to become fully established. Being technically root hardy to z5 it still need very thick layer of mulch and burlap wraping in a first couple of winters. Spring/early summer planting is highly recommended for z5-6. Second, of all hydrangeas, young oakleaves are the most succeptible to root rot while still can't stand drought. Therefore, one have to find PROPER watering regimen to satisfy this requirement. Again, thick layer of mulch could be handy. Third, it blooms on old wood and you are back to square one for winter protection as you would be with the most of macrophyllas. Winter protection ala 'hayseedman' for quercifolias will be not only questionable due to the rangy pattern of growth, but most likely will be impossible for the most of them due to their sizes, assuming they'll not die back every other year. 'Alice' in particular, is one of the largest h.q. and could easily reach 8x8' in just 3 years and 12x12' in 5 years if no dieback. IMO, dwarf cultivars, such as Pee Wee or Sike's Dwarf (both look identical to me anyway) are the only quercifolias that could be/should be attempted to grow in solid z5 on condition that grower is determined and will put reasonable effort to protect them. Fourth, indeed, fall foliage of oakleaves is a site to behold. However, in order to develop fall color it should be grown in a considerable sun, say 3-4 hours, and here you'll have another contradiction. Location with 3-4 hours of tentatively morning sun in a summer most likely will become a 6-8-10 hours of sun in a winter and such exposure most definitely will dry flower buds or even the whole branches by the spring, thus you'll have a huge non-blooming plant in a best case scenario. Sorry for the doom and gloom, but that is how I see it. Re: 'Blue Billow'. It wasn't me who touted it, but Hayseedman reported that it blooms RELIABLY for him in z6 WITHOUT any protection. In my z6b garden I don't protect any hydrangeas except trying to chose location wisely, and indeed B.Billow bloomed for me the last three years on a row, including very cold winter of 2003/04.