Here is my fully automatic sugar cane farm. It uses an RFtools sensor to tell when the sugar cane is 3 blocks tall, then it pushes the blocks out behind the sugar
How to make an automatic sugar cane farm in Minecraft - Gamepur
Here's how to build an automatic sugarcane farm in Minecraft - WIN.gg
an easy sugar cane farm, you need: 16 observers, 16 pistons 16 sand 16 redstone 48 building blocks, 16 sugar cane, running water, a hopper and a chest. : r/Minecraft