Bullfrog croaking: only in springtime, or all spring/summer/fall?

The ones in my ornamental pond croak all summer long, but only in the evening. I can’t recall when it finally slacks off.

Invite him to a BBQ with the frogs.

The croaking can go on all year, but it is worse in the spring when they are trying to attract mates.

I think bullfrogs hibernate in the winter. The croaking is to attract mates and is a territorial thing. I seem to recall something about the temperature determining when frogs start/stop croaking. Sort of like a built-in basal thermometer alarm system.

Yes, it is generally a mating and territorial thing as @WestRiverrat said.
My neighbors have a big pond with some bullfrogs, but mostly it is the gazillions of Pacific tree frogs over here, they are everywhere and the spring peeping starts as early as Feb. and goes for months. Simmering down now as all the frogs have already laid their eggs, then, in June/July the yard will be swarming with eensy weensey tree frog babies. I love them!

Oof. These ones croak ALL night. Well, at least it will only happen half the year or so.

@marmoset you will get used to it, then you won’t hear it until it is gone. Just like city folk learn to sleep through all the sirens and noises of the city.

We used to have this problem – a neighbor with an ornamental pond – loud annoying frogs in the evening when you are trying to sleep.
There is a simple solution but you need to get your neighbor’s OK.

There is a general purpose fertilizer called Sulfate of Ammonia or Ammonium Sulfate. It’s looks like a white crystal granules or kind of like rock salt. You can buy it at home depot or lowes for pretty cheap. Good stuff to make your lawn turn green in winter too – it’s like nitrogen steroids for your lawn….anyway….toss some of this stuff all around near the pond (but not in the pond if there are fish in it) and also not too much that it will burn the grass or plants around the pond….basically where the frogs would approach and or hang out near the pond. Don’t water it in. Let it remain undissolved on the surface near the pond. When the frogs approach the pond they will step into this stuff and it will disslove on their skin and irritate their skin. They won’t want to get near the pond after that. You may have to reapply if the sprinklers or rain dissolve the initial application. The key is, you want the frogs to come in contact with the dry crystals to repel them.