Annuals thrive in both warm and cool climates and are categorized as either cool-season or warm-season, based upon their hardiness and ability to thrive within cool soils. Cool-season annuals include flowers like pansies and primrose that have the ability to withstand a heavy frost. Warm-season annuals are flowers like zinnias and impatiens that flower best in the warm months of spring and summer.
With spring come the first signs of flowers shooting up through winter's layer. A gorgeous spring annual is the petunia. The petunia is a trailing plant that grows up to 18 inches in height and 14 inches wide. Placed in a hanging basket, the petunia is a brilliant bloomer that blooms in a wide range of colors, including white, red, yellow and lilac. Some petunias are variegated, meaning they have more than one color swirled together to create a brilliant bloom. Petunias also have a moderate drought tolerance, making this annual ideal in arid climates.
Alongside the petunia, plant the ever-colorful California poppy. California poppies are a spring-blooming flower that prefers sun to partial shade. Poppies grow up to 24 inches in height and are ideal along the back of an annual bed or growing inside a container.
Annuals like zinnias are the perfect drought-tolerant summer flower to grow inside the garden for long-lasting blooms. Zinnias are also among the easiest flowers to grow from seed and produce colorful flowers that are perfect for a fresh-cut bouquet. Scatter zinnias alongside a garden wall or among a perennial garden for bright bursts of color.
Next to the colorful zinnia, plant the ever-colorful New Guinea impatiens. These summer annuals are grown in a wide range of stunning colors, including hot pink and bright orange. The green to bronze foliage accents the lovely flower and is a summer must for any garden. Planted in summer, the New Guinea blooms until the first sign of cold weather.
Fall annual flowers nestled within a flower garden and in containers add bursts of bright color around the landscape. A colorful and low-maintenance annual flower is the pansy. Pansies come in a range of colors and are known for having a "face" on their petals. Small pansy blooms, also called Johnny-jump-ups, are miniature pansies with delicate blooms. These small flowers are ideal tucked along a front flower bed and other small spaces that need color. Around the pansies, add ornamental cabbage plants. Ornamental cabbages have a textured appearance that resembles a cabbage. Its multilayered leaves pop open in fall for an elegant design and texture alongside the pansies.