Why won't this sapling grow?

[Amalthea]

I have a perfect apple orchard behind my house. Tutu moved in on top of it and destroyed some of the trees; after she moved, I replanted them in the exact same spots, but one of them won't grow; it keeps dying, and I have no idea why.

It has 9 spots of grass around it; I can try to post pictures if it helps. Does time travelling affect tree growth? Because none of my other saplings died from time travelling. Is there a limit to how many perfect fruit trees you can have in your town at once? I have no idea why this is happening.

 

[Hoppy~Shnell]

I don' believe you can surround a tree with other trees.

X = Tree
o = Grass
Y = Will not grow

XoXoX
ooooo
XoYoX
ooooo
XoXoX

D-does that make sense? ._.

 

[Amalthea]

I don' believe you can surround a tree with other trees.

X = Tree
o = Grass
Y = Will not grow

XoXoX
ooooo
XoYoX
ooooo
XoXoX

D-does that make sense? ._.

I'm not sure that's true, because I had a 6x4 fruit orchard where the trees were aligned perfectly on top of each other.

I actually just found out that I planted the fruit a spot over from the spot where it was before Tutu, but... I'm still confused as to why it wouldn't grow there.

 

[Cudon]

The area might be too ''busy'' with other trees/bushes around it. I've had similar happen and you can fix it by destroying some of them and then putting them back one by one. You kinda have to guess which other trees are causing it though and it can get annoying.
For some reason trees that have been planted from 1k bell bags don't get affected by it so you could plant one and then see if it can grow there.

For me killing 2-3 bushes on the other side helped when my bushing didn't wanna work

 

[Mikorin]

Y in that equation will grow as long as there is an open space along one side. You have to plant in rows, or just don't plant the middle last. I don't know if that's your problem though.

 

[Amalthea]

The area might be too ''busy'' with other trees/bushes around it. I've had similar happen and you can fix it by destroying some of them and then putting them back one by one. You kinda have to guess which other trees are causing it though and it can get annoying.
For some reason trees that have been planted from 1k bell bags don't get affected by it so you could plant one and then see if it can grow there.

For me killing 2-3 bushes on the other side helped when my bushing didn't wanna work

I wonder if it has to do with the order you plant them in? Like in Hoppy~Shnell's diagram, maybe if you plant all the X's first, the Y won't grow, but if you plant them in a different order, the Y sapling can grow.

How weird! Learn something new every day

I think I figured it out, though. I'll just have to not plant the middle last. Thanks everyone!