Q.Can I plant a hydrangea that has developed hair roots from a cutting?
I cut 3 blossoms from my hydrangea bush and put them in a vase of water. By changing the water every few days and trimming the stems,they have stayed as pretty as the day I cut them. I noticed that 2 of them have tiny roots. I am wondering if they would grow into another plant if I planted them in potting soil?
Yes, you can plant into pots of potting soil.
This article will help you.