There’s multiple types of “fertilizer”.

Ammonia is made using liquid natural gas.

Potash and Potassium are both mined, we break up rocks that have held the good stuff for millenia or far longer.

There’s a shit ton of environmental concerns with the mining, then the fossil fuel usage to move it around, then the fact almost no one reclaims it so we’re dumping it all in the ocean where it fucks up that ecosystem.

But most importantly the ecosystem is adapting to that constant and steady supply, even tho eventually it’s going to stop. Either because we finally wise up, or something like WW3 happens and disrupts global shipping.

Like, pretty sure China controls the potassium supply these days, most countries like England burned thru their supply already.

You think Iran cutting off oil is bad? Wait till China decides their potassium is best used in China.

We can live without oil, if the planet has to live without fertilizer most complicated life forms (human and otherwise) won’t be on it.