I'm working on farm designs, and my current design has a stream of water from the ceiling flowing down onto fully grown carrots and pushing them to the side.

But if the water runs for too long, can it turn the farmland back to dirt? I think it could in previous Minecraft versions (I'm in 1.11.2), which is why I'm wondering now.

I watched over my design for a little bit (about 1-2 minutes), and when I got rid of the water, the farmland was still intact.

1 Answer

Via the wiki page on farmland and its decay:

Under certain conditions, a farmland block will "decay" becoming a dirt block, regardless of its state of hydration. This will happen if any of the following occur:

If the farmland block is dehydrated and nothing is planted on it for too long.

...

After some testing, Farmland will only decay once there is no hydration and no blocks above it after a certain about of in-game time. By putting water on it, it thinks there is a plant there and will not decay.

However, do note: this does not hydrate the water itself.

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