Either a) or c).
In z7 it wouldn't make much of a difference.
Keep in mind that if you chose c) you'll have to water them a few times during the winter.

Thanks Ego35 and Mary!
Ego - If I plant them in the ground now, are there any tips other than a good mulching that I need to do to get them through the winter? Fertilizer, etc? If it works in CT, I don't see it having any problem here!

Mary - We just moved from Atlanta, so I know what it's like to work with that clay! So glad I don't have to dig in that anymore! That said, I had no problems with transplanting hydrangeas there (7b) - winters are much longer & colder than there which gave me pause as to what to do. I have a feeling that that technique will work here, and would be much better than my garage idea, but if I can get them in the ground now it will simply be less work all around.
Thanks!

Water and mulch... and water in August-September. That's it. Just for your own peace of mind, when/if temperature drop below 10F in a mid-winter cover them with an upside down 2G pots.
Good luck!

Status update:
Planted the three biggest in the yard on the 27th, they are doing GREAT. Planting up the rest this weekend, will post how it goes in the fall....

I think you're right to plant them now.

I took some cuttings from a Blue Billow one summer and planted them out in the Fall, mulched them really heavily for the winter and they did just great.

Hay

I realize this is a very old thread, but I'm bumping to see if anyone has any other comments or critiques to the above advice. I rooted several panicle hydrangea cuttings and it's time to move them outdoors.

Should I place them in larger pots?

Should I plant them in the ground?

Full-sun, part-sun, full-shade?

I am unsure of their final location; some are gifts others are for fun.

Guess I am just curious to hear other thoughts and best practices.

Thanks.

From what I have read in the books I have on hydrangeas, tender first year rooted cuttings likely won't survive their first winter in the ground, even protected in colder zones. I have some in the ground that I don't mind to lose as an experiment but I don't really look for them to survive. Their roots are excellent though so I might get lucky. Most of them I already planted had roots the size of both of my fists together. I will be keeping my more coveted young plants inside the house in a mini greenhouse to grow under lights all winter and will plant them out in the spring after the threat of frost has passed. One book I have suggests protecting young hydrangea cuttings even further by not planting them in the ground until after their second winter. I won't be going that far as I live in zone 6b, but for colder zones that may be a good idea. You can keep young plants in an unheated outbuilding or garage. Or in an unheated greenhouse or cold frame. Or even a heated greenhouse if you are lucky enough to have one. =]

Once you do plant your hydrangeas, plant in part sun. Morning sun, and evening shade for best flowering. As far as putting them in larger pots right now, only move them if their roots have already filled the pot they are in. Once their roots fill the pot they are in, move up to the next sized pot. There is no need in planting a tiny rooted cutting in a huge pot. Too bulky to have to lug around.

I have one Limelight (hydrangea paniculata) cutting that rooted and I went ahead and planted it. My cutting has already hardened off and became woody on the bottom half of the plant and it's roots are fairly large. If it doesn't survive I will take another cutting next year. I just don't have the room inside for all my cuttings. lol

Steppskie...you said time to move them outdoors. If you've had these inside any length of time, move them out gradually so as not to risk damage from sun and wind. Introduce them back into the elements over several days, increasing the amount of exposure each day.

Thanks for the replays so far.

Kayla, thank you for sharing your experience. If I plant them in the ground, I have a bright-shade location near my foundation that may be well suited this winter. I may try the garage; I'll have to figure out the watering schedule.

Morz8' thanks for mentioning the "hardening off" part of moving them outside. Thanks for the comment.

Anyone else have a successful best practices comment?

Last year I planted my 10 layered cuttings (paniculatas and macs) directly in the ground once I saw some roots. They all survived my very cold winter (with just 2 inches of compost over them)...most of them had to grow from the ground up....they are now the size of 2 gallon plants that you would buy from the nursery (especially the macs). Ironically, the ones I had in pots and wintered in the garage did not survive!

Soil of small plants/cuttings can dry out easily in garages much more easily than larger pots. Thin or small stems can also permanently dry out. Best I can recommend is feel the soil every now and then when you're coming or going and give it a cup of water every couple weeks.

I got a starter of Mac 'Blarney Stone' from Hirt's recently and it's seriously just a little plug. Has a 4x4" root ball but I'm worried it might dry out. Maybe I should suck it up and plant it and cover it with a few leaves during the winter. Can't dry out that way!

My cuttings are still very small; cannot see roots outside of my 4x4 planter. I will start to reduce humidity on those that are showing great new growth. Then I will start hardening off. By fall I will hopefully be able to move them outside, but I am concerned about them not having time to establish. Any pointers regarding the latest time to plant these outside?
And yes, garage is still an option.

Earlier the better, I'd venture. But if planting "now" you just don't want to roast the plant, so a temporary shaded location may be required.

Springwood, my LA Dreamin came in a tiny 2.5" pot. It has had some top growth but not much root growth. Is it too young to plant out?? I hate having to keep so many plants in the house. I am i zone 6b but do not want to lose my plant.

Planting even where I said would be a risky venture. If it were mine I would try starting it in a gallon pot for a year or two, overwintering in a cold but not frozen place. Wish I could point folks toward a larger one. One place in my area just put 5-gallons on sale for $42!

I am in the PNW - Just north of Seattle, z8b. I keep most of my cuttings in pots for the first year or two. But I move them up from propagation tank to 4x4 and then to gal. If you want to know if you have roots - gently dig them up with a dibble or chopstick and look! You won't hurt the plant and will know if it needs to be potted up - moved to larger container - or not. Some I will bring into the garage and water when I go by and check the soil. I have had the soil actually ice in the basement and all the cuttings survived just fine. As long as the water drains it will be ok. If I had some that I really wanted to make sure they made it through the first winter - I would take some in and leave some outside under cover of mulch, leaves or even foam packing material. Sort of like not putting all your eggs in one basket! I have also wintered some at the edge of the heat mat when I was concerned that they might not be big or strong enough to make it through some really cold temps. Good luck and please let us know how they do.

They are very small, as I said before, but I have new growth on 4 of them. I am beginning to think that a rough winter may do them in. Although they are flourishing now, I think my garage may be the best place for them this winter.
In the meantime, should I start reducing humidity soon?
Should I place them outside for just a bit during fall months?
I assume I place them in the garage when they are dormant, but do I encourage dormancy?
I have never overwintered anything indoors before, and am hoping I will be prepared to do so before that time comes.

You can bring them in when it starts to get cold or dark. Most plants do not use the temperature as an indicator for life cycles, going dormant - emerging from dormancy but use the length of daylight. So, when the days get shorter and shorter and darker - bring them in. I don't worry about how wet they are when I bring them in - after all, in Seattle it might be very wet when they come in - lol. Some I will put under lights and on heat mat and those never go completely dormant and I don't see a difference in how they do in the spring compared to those that went completely dormant. The old leaves fall off when the new ones emerge. In our mild climate (PNW 8b) I push a lot of cuttings into established pots of other plants and leave them in for a year or so and they also do just fine. Over the year I may start 20 - 30 or more plants and since I give them away and don't sell them, I am pretty casual about the process. My biggest problem is keeping the labels with the plants. If that happens I have to wait until the first bloom before I have a clue what the actual name of the plant might be but I never get complaints. lol