Cut hydrangea flowers that appear in florist's bouquets tend almost always to be macrophyllas and I see nothing in your photo to convince me otherwise, So not a great choice for a zone 5..

Pretty easy to grow from cuttings, including bits from a bouquet. But you'd have to protect in winter.

Thank you, gardengal! That figures. Boo. lol! They make great cut flowers!

Floral, I noticed fresh leafbuds so I potted up the cutting already. :)

You can always root it and hrow on a pot.