Roses in Vase Growing New Leaves?

September 19th was my birthday, and my daughter graced me with six beautiful long stem roses. The roses came together with some plant food. I carefully placed my beautiful roses in a vase with water and added some of the plant food. I replaced the water with more of the plant food after 4 days and today (Sept. 30) as I saw that the roses were dry I decided to store them in a secure place.

As I emptied the vase, I was carefully drying the stems when i noticed that the stems were growing new leaves! I had never seen this happen before so I quickly placed new water in the vase with the remaining plant food. How soon should I plant the rose stems in pots? Thank you so much for all your assistance.

Sincerely,
Grace