Assertion: canna's flower | /r/HasProperty | pruned
Facets:
Source sentences:
text: Over the last 150 years, breeders have reduced the height of the plant, increased the flower size and staminode width, increased the length of the flowering period, improved the flower placement (higher above the leaves and more erect), improved flower durability, improved the cold hardiness, and produced self-cleaning plants (the spent flowers fall off automatically and do not need to be pruned).