If you place a sugar cane in a water tile (with dirt under it) you can place the sugar cane. This even works many water blocks down. like shown in the pictues
Environment
Rivers and lakes, probably oceans too
MC-103189
Sugar Cane in water
Resolved
Duplicate
0
(Unassigned)
Unconfirmed
Minecraft 1.10 Pre-Release 1, Minecraft 1.10 Pre-Release 2
Retrieved
Yes! Came here to report it, searched for it and you have already found it! Added some photos because I had them.