A batch is a quantity of cannabis or cannabis product that is treated as uniform for testing and tracking. For flower it usually means one cultivar from one harvest, dried and cured together, up to a maximum size set by regulation. For extracts it means one production run. The batch ID ties the physical product to its COA.
In practice
Check that the batch number on the package matches the COA. A COA for batch A says nothing about batch B, even of the same cultivar from the same producer. Regulators commonly cap batch size (for flower, often a few kilograms to tens of kilograms; check local rules) and set how many sample increments must be drawn. Mixing material from different harvests into one batch undermines the meaning of the test. For home growers, "batch" simply means the harvest you're describing, a useful habit when keeping records or sending samples.
Don't confuse with
- Cultivar: genetics; one cultivar yields many batches.
- Sample: the portion taken from a batch for testing.
- Run: a grower's word for a grow cycle, which may produce several batches.