Grow a Garden Event Timers

Fresh seed rotation — rare seeds like Beanstalk can appear in any restock.

Pet eggs rotate — Mythical eggs are the chase.

Every 1 hour, on a fixed UTC clock. Wiki: "Every hour on the clock, the Admin Board starts a random weather and restocks a random seed/egg/gear." — https://growagarden.fandom.com/wiki/Admin_Board

Every 1 day, on a fixed UTC clock. Wiki: "The merchant will definitely spawn in 12 a.m. everyday (GMT +0:00)." — https://growagarden.fandom.com/wiki/Merchants

Not on a timer of its own: each Night cycle has a 1-in-3 chance of coming up as a Blood Moon instead. Night runs six times a day at 00:30, 04:30, 08:30, 12:30, 16:30 and 20:30 GMT, so those are the six windows to be online for — expect roughly two Blood Moons a day. Lasts 10 minutes and turns six crops Bloodlit, one every 40 seconds; a Night Staff raises the yield.

No fixed schedule.

Random natural weather, not a scheduled event. The wiki's own estimate is "approximately every 20 minutes" and it flags that as unconfirmed observation, and any given rain roll can come up Frost (25%) or Thunderstorm (10%) instead. While it runs, growth is 50% faster and each crop has a 50% chance of the Wet mutation.

No fixed schedule.