Sedirea japonica in bud

Naomi and I both bought Sedirea japonica last year as large seedlings and thougth it would take years to get them to bloom. For some reason, my plant got a flower spike about three weeks ago. My plant's sister plant over at Naomi's for some reason doesn't have a bloom but instead is getting a new leaf. Something triggered my plant to bloom... I am trying to figure it out and think it must be warmer temperature because I brought mine into my greenhouse from it's usual window spot when I went on vacation and the green house is much warmer then my window spot. Anyway, I can't wait to see it bloom, it has a spectacular flower that is supposed to smell great too-