Saplings?

[milkchunks_]

I'm trying to place four spruce saplings to make a big tree, but I can't place them next to each other? I've been having this problem for a while, I have to place them far away to each other, or sometimes I just can't place them at all. Is there a cooldown or something?

 

[milkchunks_]

Never mind, I think it was because there were blocks above them