Q.Northern Catalpa tree flowers
We have very large Catalpa trees. When they flower and heavy rain or winds come through, large clusters of the flowers fall. I know I can’t save the individual flowers that fall, but the clusters with small stems I’d like to gather and put in water. However, when I do this, the flowers don’t flourish like other flowers when put in water and die within a day. Is this just something I can’t do or am I doing something wrong? Seems such a shame that they can’t survive a few days in water.
Here's an article with some tips you might consider:
https://www.gardeningknowhow.com/ornamental/flowers/fgen/flower-food-for-cut-flowers.htm