These showy flowers are produced from underground storage structures known as bulbs, tubers, corms or rhizomes. Most have a blooming period and a rest period where the plant goes dormant in preparation for next years bloom. Fall bulbs such as Daffodils, Bearded Iris, Anemones and Tulips are planted in early fall for spring bloom while Spring bulbs such as Gladiolus, Dahlias and Lilies are planted in late winter to early spring for summer bloom. For a more dramatic effect, plant bulbs in large groupings of a single variety.