This is a bug I recently discovered .
When you have Water in Dispensers and you Dispense them , you can place Sugar Cane to a Dirt , Grass Sand or red Sand Block next to it .
When you turn off the Water again sometimes is stays there for a while .
It'S a bit weird .
But you maybe are currently fixing this problem because in 1.6.2 or 1.6.4 all the Sugar Cane stayed there forever .
Thanks for reading .