By a size band in millimetres, with a stated measurement convention, a tolerance for
the fraction outside the band, and a separate limit on stem length.
The measurement convention is the part that gets missed. A floret can be measured
across the head, across the widest dimension including the stem, or as a maximum
dimension in any direction, and the three give different numbers for the same piece. If
the specification does not say which, the supplier will use the one that is easiest to
meet and neither party will be wrong.
The tolerance matters because no agricultural product grades perfectly. A band with no
tolerance is unachievable and will be ignored, which is worse than a realistic
tolerance being met. State the permitted percentage outside the band, and whether
undersize and oversize are counted together or separately – buyers usually care more
about undersize, since fragments look like waste in the pack.
Stem length is the clause that most affects perceived value and the one most often
absent. A floret with a long stem is cheaper to produce and looks worse in the bag. Set
a maximum, and say whether it is measured from the base of the head.
Finally, specify the head colour requirement against a physical or photographic
reference standard rather than in words, and add a limit for yellowing, which is the
characteristic broccoli defect and develops from raw material that was held too long
before processing.