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.
There are many kinds of flowers which have been called Lilies but many of these so-called Lilies such as the day-lily, water-lily, and arum-lily, actually belong to other groups of flowering plants. Plants in the Liliales grow from bulbs or corms, both of which will store food over the winter or during the dry season.