Something interesting happened at work...

So a customer at work shows me a cut flower and asks what is this? Well, it's late, it looks obvious (in my mind) that it's an Annabelle Hydrangea. The customer even agrees "yes that sounds right." I show her the Annabelle Hydrangeas and "Oh! They're too big!" Hmm? Apparently hers grow to maybe 3' tall maximum with flower cluster (corymb) no larger than about 5" (The one she had brought in was only 3"). The leaf on the stem she had was also about a quarter the size of the leaves on the plants we had in stock. Cultural differences? Made sense but I checked with my supervisor and he noticed (very quickly) that each flower on her plant had only 3 petals (apparently they are bracts) compared to the usual 4 found on 'Annabelle' and 'White Dome' (which it definitely wasn't), the only two Hydrangea aborescens cultivars we carry (and 'Grandiflora' according to Google). She was looking for more of these but I don't think we'll be able to help her - we have no idea what it is (yet!) but I'm pretty sure I want one.

[Update] Apparently I was closer to being right. After careful observation of any and all 'Annabelle' hydrangeas my supervisor and I saw it appears these differences in plant size, leaf size, number of flowers and number of bracts per flower are all basically a result of cultural differences and the customer's hydrangea is almost certainly an 'Annabelle' hydrangea.