It's only when the water level hits 0 that the flower dies. Also, a flower needs in general 2 cycles of the sun. So I when I'm in the second cycle, I don't water it.
I discovered that the reason I haven't been able to water the tree is because I was standing in the wrong place. I thought this whole time that I had to stand right at the tree but I needed to stand to the left of it I guess.
edit: never mind, I was wrong. Sorry but I'm just gonna give up.
