How close to a water block do my tomatoes need to be to be count as irrigated in Dragon Quest Builders 2?

2 Answers

The water block needs to touch the planted block in order to be naturally irrigated. Water also occasionally falls from the sky ;)

Also, also, if you have a way to carry water, you can literally pour it on your crops, then just scoop it up again if you don't like the water sitting around everywhere.

I don't irrigate them at all, the people in the village water them, if it is marked as field. Irrigitation would probably remove the need to water them.