Assertion: iceberg lettuce's head | /r/HasProperty | immature
Facets:
Source sentences:
text: A very loose head is immature and a very firm or hard head is overmature.
text: Heads that are immature and mature have much better flavor than overmature heads and also have fewer postharvest problems.
text: Heads that are immature and mature have much better flavor than overmature heads and also have fewer postharvest problems.
text: A very loose or easily compressible head is immature and a very firm or hard head is overmature.
text: Harvest crisphead, cos, and butterhead lettuce when the heads are firm and mature.