Earlier, I had tried to make big 2x2 spruce trees, but I was just wasting my bonemeal; it seemed like it was impossible, but as it turned out that, since I was in a snow biome, the snow layers and perhaps grass just around (on the same block height as the saplings) were interfering (despite regular spruce trees handling this just fine, and java last I remember). And later when I was trying to make iron golems for my sister, it turned out the snow layers under the iron block arms were the culprit.

These types of blocks shouldn't cause these problems but they do.

2x2 spruce trees need a ring of 4x4 around