Daylilies (Hemerocallis sp.)
There are over 60,000 registered cultivars of daylilies. Luckily for the survivor wandering deserted urban areas and spotting these hardy flowers, they can be a food source. The flowers are edible and can be dried and saved for later. Young leaves and tubers can also be eaten.
If harvesting from an urban landscape, however, be sure to avoid plantings near what were once heavy traffic areas where contaminants and runoff would likely be absorbed by the plants.
Daylilies for Pre-Apocalypse Folks:
Most daylillies occur in clumps 1 to 4 feet high. Linear leaves grouped in opposite fans. Flowers generally have three petals and three sepals. Mostly used for colored flowers. Can be used as a perennial flower border, planted in large masses, or as a ground cover on slopes.
Daylilies can grow in many environments, but are often distanced from trees or shrubs that would compete for moisture and sunlight. Best in full sun, can tolerate light shade. Can tolerate most soils but do best in slightly acidic soil high in organic matter. Prefers well-drained but moist environments. Can spread aggressively.
Can be planted almost any time soil can be worked. Dig hole large enough for the roots without bending them.