Sugar cane can be planted in a liquid if there is water adjacent to to it and one block lower

You are able to place sugar cane inside a liquid if there is water adjacent to it and one block lower. In the fourth picture the sugar top sugar cane will pop off if there is a block update or a random tick, because there isn't a water block adjacent to it and one block lower.

 

NOTE: To reproduce the result shown in the last image you have to place the top sugar cane first.