In message , MikeCT
writes

"June Hughes" wrote in message:
snip
On Friday, we noticed a small plant (definitely a hydrangea) growing in
the place where the 'dead' plant had been. I am very happy about this but
wonder if anyone can give any advice as to how best to keep it going. Many
thanks in advance.
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I wouldn't do anything to it until the autumn, after it has
dropped its leaves. Then very gently dig down around the plant,
saving as many young roots as possible, remove and pot up.
You might find that the young plant is growing from part of the
original hydrangea's root left in the ground. If that's the case,
cut the little hydrangea away with the young roots.

Great Mike, thanks. I am very anxious not to do anything to upset it.
--
June Hughes