Assertion: cardoon's flower | /r/HasProperty | open
Facets:
value: during the night
type: TEMPORAL
value: for about 18 hours
type: TEMPORAL
Source sentences:
text: The flowers of both cacti open at night and stay open for about 18 hours.
text: The flowers, like all the flowers of the columnar cacti of North America, open in late afternoon, remain open during the night and forever close by noon of the next day.