About Annual Flowers

There are more than 100 annual plant varieties. Some tolerate drought, some attract hummingbirds and others attract butterflies. Annuals grow for once season and die. Annuals need replanting each year, except for some varieties that reseed.

Drought Conditions
Drought-tolerant annuals survive in arid conditions. However, different annuals have different levels of tolerance. Annuals with low drought tolerance include snapdragons, calendula and geraniums. Annuals that have a moderate tolerance for drought conditions include petunias, zinnia, scarlet sage, marigolds and cockscomb. Annuals with a high drought tolerance include statice, moss rose, Madagascar and California poppy.

Attracting Hummingbirds
Annual balsams are used in gardens for their colorful flowers of white, red, purple, pink or rose to attract hummingbirds. Begonias with white, red or pink flowers, and the annual geranium with white, salmon, red, pink and bicolor flowers attract hummingbirds to the garden, as does the bleeding heart, buttercup and tiger lily.

Attracting Butterflies
Nectar flowers attract butterflies. Candytuff with white, red, pink and lilac flowers provides nectar for the butterflies. Other nectar annuals are spider flower, cosmos, daisies and four-o-clock annuals. Host flowers for attracting butterflies to lay eggs include flowering cabbage, pansy, sweet alyssum and toadflax. Toadflax is an annual with yellow, white, red, pink, orange and bronze flower colors.

Seed Annuals
Annuals planted from seed take five to 21 days to germinate, depending on the variety. Geraniums take seven to 21 days, while four-o-clock annuals need five to seven days. Soil temperatures must be between 70 and 75 degrees, except for melampodium and bachelor's button, which needs soil temperatures between 65 and 70 degrees.

Reseeding Annuals
Reseeding annuals are left in place until the plant drops its seeds in the soil. The seeds are left in place during the winter and germinate the following year when the soil temperature and weather is right. Reseeding annuals include morning glories, petunias, summer cypress and cornflower.

Source: http://www.ehow.com/info_8024014_annual-flowers.html

Definition of Annual Flowers

Annual flowers are flowers that finish their life cycle in one growing season. Annuals are usually classified into three groups: hardy, half-hardy and tender.

Types
Hardy annuals thrive in cool weather and are usually planted in the fall. Half-hardy annuals can endure light frost; they are generally planted in early spring. Tender annuals die in freezing temperatures and are planted in the spring.

Examples
Zinnias, petunias, pansies and sunflowers are a few common annual flowers.

Advantages
Annuals are relatively inexpensive, versatile and hardy. They are also easy to grow and are very colorful.

Disadvantages
Annuals must be replanted each year, which can be expensive and time-consuming. Some annuals need maintenance to continue blooming through an entire season.

Considerations
Some perennials (plants that live for more than two years), such as begonias, some impatiens, a few snapdragons and geraniums, are sometimes grown as annuals in climates where they are not hardy enough to survive the winter.

Source: http://www.ehow.com/facts_5590058_definition-annual-flowers.html