Their presence is expressed as a percentage. A LOW percentage, preferably none, is desirable. Standards of germination for certified seed are established by the Kentucky Seed Improvement Association. Most hard seeds eventually germinate and produce a plant. Hard seeds extend the germination over a longer period of time, which may or may not be an advantage.
Hard seeds are undesirable when immediate germination is required.
Conversely, presence of hard seeds would be desirable when an extended germination period will increase the chances of a stand. The sum of the germination and hard seed percentages is the total value of the seed lot with respect to plant-producing potential. Percentages of germination and hard seed must be reflected separately on the analysis tag. The month and year the germination test was made. Generally, the germinating or plant-producing ability of seed declines with age.