From what I understand, the 12-in-a-row limit only applies to bushes, trees, and bamboo. Flowers, Clovers, and items don't contribute towards the chain.
It seems like you're still confused from when I said a "hole in the chain". I meant a gap. Not a hole you have to dig. There just needs to be space (or more) with no bush/tree/bamboo to keep the chain from getting too long. You can either keep that space with nothing on it, or you can put a pattern tile, or you can plant a flower/clover, or drop an item. It just can't have another bush/tree/bamboo.
So having 10 bushes, then a gap, then 12 more bushes should be fine.