Darren’s answer is pretty thorough. Thanks Darren
The food vendors usually close based on crowd attendance and weather, but very few are open when the gartens close down. All gartens are closed by midnight, but may close a little earlier if crowds are thin. If you want to choose from all options then get there before 9 probably. Late night eats are scarce usually but a couple vendors each year usually stay open till maybe 12:30. Don't count on it though.
The vendors appeared to close at different times however they all tended to stay open write late to accommodate some of the traffic that was late to the festival.
I couldn't say it better than Darren.
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