English plurals. English nouns are inflected for grammatical number, meaning that if they are of the countable type, they generally have different forms for singular and plural.
Growing Daylilies. We'd describe the Daylily as the backbone of the perennial garden except that would do a disservice to this most durable plant -- backbones, as every gardener knows, are fragile things, whereas Daylilies are close to indestructible.
Zantedeschia are relatively hardy plants, but some are more winter-hardy than others. In this regard there may be considered two groups, a hardy outdoor group with large white flowers (arum lilies) and less hardy group with white-spotted leaves and flowers in many colours (calla lilies), such as yellow, orange, pink and purple.