Lag phase

For several hours after yeast is added to fresh wort, you won't see much happening. This is called the lag phase, and it's similar to changing time zones or elevation. A sudden transition from one environment to another takes a bit of getting used to, both for people and for yeast.

Much of the beer’s character is determined at this time as yeast cells absorb nutrients from the wort and prepare for growth.

Expect the lag phase to take anywhere from 12 to 48 hours.