I'm no expert my any means, but I just planted two new hydrangeas two weeks ago. I've been keeping them watered and they look great.

I would prune the hydrangea back now, if it does bloom on old wood. But, I'd also transplant it now..based on the fact that my two are doing really well. Just be sure and keep it well watered.

From what I can find, Sister Theresa hydrangea is a cultivar of hydrangea macrophylla. This type of hydrangea sets flower buds in the summer for next year's flowers. Therefore, if you prune it too late, you will cut off next year's flowers. Best to prune it very soon in preparation for the move.

To learn more, just research how to prune hydrangea macrophylla.

Here is a site with some pruning tips from a couple of very experienced Hydrangea growers, Kristin & David VanHoose at HydrangeasPlus. I have used this method and it works very well. However, I did not move any of mine. Sorry to say that I mistakenly purchased a Sister Theresa from a local highly recommended source and it was a dud. Nurtured it for several years and it never grew larger or produced any blooms. It is now compost somewhere in the garden. A different replacement cultivar, from HydrangeasPlus was planted in the same location and it is now a very large shrub, covered in blooms each year. BTW, 10 other Hydrangeas, a total of 11 of 12, purchased from that same local source, wound up in the compost heap. Either, they died or never grew larger and never bloomed.
Rb

Here is a link that might be useful: Pruning Tips

Razorback, thanks for the pruning tip site. I am going to start a couple of cuttings when I prune the Sister Theresa. Let me know if you want one of them. I haven't had luck with other cuttings this year, but surely I can get hydrangeas to work. Be happy to give you one. Of the original two I purchased, one took off the first year. The other looked miserable. I moved it and it was much happier. I've had both of them for four years now and both are doing very well. If yours didn't do anything for several years, it was a dud. What was the local source? I want to put some hydrangeas in the back yard and want to avoid that source.

Thanks SugarHill, for the generous offer, but I have Madame Emile Mouillere, a mop with large white flowers and a half-dozen or so large pretty blue lace-caps scattered about on it.
I would recommend looking for bargains now that Pikes and Lowes has sales on their Hydrangeas. Purchased a dozen recently at Pikes on Lawrenceville Hwy(east of Jimmy Carter) at 20% off. Some were cultivars that aren't available elsewhere('Sweet Chris'a/k/a 'Big Smile', 'Sun Goddess'(Syn:'Lemon Zest', 'Yellowleaf'PPAF), 'Chiffon'(Syn: Shichidanka', Shichi danko nishiki' and others. Sign indicated that 'ES' and 'Lady in Red' was also on sale. I didn't buy any of those. All were large plants in gallons and less than 10$ ea.
Rb

Sugarhill,

I could trade you a Sister Theresa baby for an Endless Summer baby if you are interested email me. I'll save one of the cuttings I recently started. Or if you prefer I can start an Oakleaf hydrangea for you.