Minecraft – Does grass grow when covered in water

minecraft-java-edition

I was playing around with the idea of make pistonless automatic street lights in Minecraft. My idea was to use a BUD switch to see if a grass block had grown or died.

I know that if grass is underwater during night it dies, but I dont know if it grows back during the day if it's still underwater.

I would also appreciate it if you had any suggestions for non piston BUD switches, the ones I have been trying to use are not ideal because they send out pulses.

Best Answer

For a start, if you're looking for a light sensor that toggles, then look at this video.

Grass needs light level 9 to grow, so in direct sunlight, with a single layer of water will reduce the light to 12 (1 because it's not the top block and +2 because of the water), so will still grow, but having a second layer will make it now 9, so will mean it takes a while to grow, because it is only just allowed to.