Apple trees aren't growng apples

[ropes]

I've been checking my apple trees every day, have put down a large sprinkler and yet they are refusing to grow apples. How long is the growth rate of apple trees?? I feel like I'm going mad but it's basically meaning I can't progress through the brewing profession :(

[MortVent]

trees need fertilizer, same as vines

You have to load the sprinklers to automate the fertilizer

[DarkOutX]

Later, for next tier plants to grow, you will also have to put beehives near it
It doesn't needed for Apple Trees, but anyway.
To understand which plants need fertilizer, and which need beehive, just look at animation in seeds description (some of them will have beehive in background)

[soratoumi]

As for which produce requires beehives, if you plant a seed
1) notice a white dotted line
2) your character has a bee icon pop up by the head
it means it requires beehives within the range.

https://lumaisland.wiki.gg/wiki/Farming
This link will take you to a page with information on which fertilizer is good for which tree/vines.
(it's a link to a luma island official wiki site. It's still on the works for some info.)

[Kayo]

Each tree have specific fertilizer it needs , and some tree need the bees to grow.