Assertion: onion | /r/HasProperty | perennial
Facets:
value: most frequently
type: DEGREE
value: by nature
type: OTHER
Source sentences:
text: In either case, be sure to place the winter onion bed at the side or end of your garden because these onions are perennials.
text: In general, all onion plants are either biennial or perennial by nature.
text: The onion is most frequently a biennial or a perennial plant, but is usually treated as an annual and harvested in its first growing season.
text: The onion plant is a perennial herb growing to about 1.2 m in height, with 4 to 6 hollow, cylindrical leaves.