Joe, If nothing else - There is the Design Master Just for Flowers spray tint line that can help to adjust the hydrangea color to your needs.
Also, I cannot recall everything she siad, but at a recent SC Teleflora Unit meeting that I attended, The presenter, Susan Overton-Ayala AIFD gave us a tip that would hold a hydrangea for up to three weeks.
I know that part of it had to do with extrmely hot water........Perhaps Carol, CHR, or another of our AIFD members on FC can contact Susan and post this information for all of us.
Thanks Rick,
Earlier this year, prior to you finding FC, I performed an experiment using white Hydrangeas and documented this experiment here on FC. If memory serves me, I kept the white hydrangeas alive and well for several weeks. Shears actually worked better than cutting with a knife.
Hot water and no preservative. I just recut the stems once a week and replaced the water once a week.
I am also familiar with Just for flowers, I just do not want to paint 300 hydrangeas, if at all possible. too much labor.
Joe