My plant barely spawns

So I made a custom cave plant that only spawns in dripstone caves. After noticing it barely spawned at all (only found like 1 in 5 minutes of scouring dripstone caves in spectator) I bumped the spawn frequency in chunks to 16 and the number of plants per patch to 25. It appears to barely made a difference at all (I barely looked, but from what I saw, there was still nothing). Did I do something wrong, did I misunderstood what those stats mean?