Annual flowers are those that complete their life cycle in only one season and then die after the first frost. Some annuals grow year-round in warmer climates, making them perennials in those areas. Annuals often are started in greenhouses and purchased by homeowners once they have bloomed. The flowers provide an array of colors to a landscape and make ideal container gardens that can be placed around the porch, deck, patio or yard in the spring.
Hardy annuals can tolerate a certain amount of frost. They can be planted in the fall, when you can enjoy them until deep winter sets in. Hardy annuals do well when planted in the early spring when you don’t have to worry about a final frost, though they may wilt during the hottest days of the summer and re-bloom as the weather cools in early fall. Hardy annuals include violas, larkspur, pansies, cornflowers and foxglove.
Half-hardy annual flowers can tolerate cool, moist weather, but may die if they have to undergo an overnight frost. It’s acceptable to plant seeds in early spring because they won’t be affected by the frost as much as a starter plant that’s already flowered. Most gardeners wait until after all signs of a frost are over before planting half-hardy seeds or flowers, according to North Carolina State University. Popular half-hardy annuals include baby’s breath, foget-me-nots, blue sage, snow-on-the-mountain and bells of Ireland.
Snapdragons are an easy way to fill in a barren landscape with color and bright greenery, and they prefer colder weather. Snapdragons fill in cut bouquets well, such as in the Deluxe Spring Forward bouquet at ProFlowers. They can withstand a long freeze once they’ve become established in your garden. Some snapdragons are grown from seed, while others are grown from cuttings of the previous year. Other cool-season annuals include geraniums and petunias.
Tender annuals are very susceptible to frost and typically are native to tropical climates. The seeds of tender annuals cannot germinate when the soil is below 60 degrees Fahrenheit. They prefer the heat of the summer and should not be planted until at least two or three weeks after the final frost. Marigolds are popular tender annual flowers because they are so dependable and grow in large bushes to fill in landscaping gaps with buttons of color. They make ideal cut flowers and typically come in white, orange and yellow. Begonias, coleus, impatiens, zinnias, nasturtium and morning glories are other examples of tender annuals.