Flowering annuals can add an explosion of color to a dull landscape. Unlike perennials, they finish their growing cycle within one growing season. These flowers are brighter than perennials or any other type of flowering plant, although they need to be replanted each year, requiring more work. On the other hand, annuals, which come in many different colors and sizes, offer gardeners the choice of growing another flower the next blooming season.
Petunias are popular flowering annuals that are easy to grow. They come in a wide range of colors and in different sizes of blooms. Grandifloras are petunias that produce large single or double flowers, while multifloras have more single or double flowers. Petunias are often grown in hanging pots or containers. This flowering annual needs lightly textured, well-drained soil and full sun. Excessive water and fertilizer can produce large plants, but fewer flowers.
The various types of zinnias come in bright bold colors and different heights. Zinnias originated from Mexico and were thought to be weeds when first discovered. Originally, they were grown for medicinal purposes, but later they were mostly used for their vibrant colors in flower gardens. While some, known as dwarf zinnias, are only 6 inches tall, others can grow more than 3 feet, according to Yardner.com. Zinnias come in all colors except for blue. They're tolerant of most soils, other than wet ones, and need full sun exposure.
Cosmos flowers, another popular annual, come in shades of purple, pink and white. While tall cosmos are used at the back of a garden, lower ones are ideal as mid-border plantings. This flowering annual has lacy leaves that add a nice accent to a garden. They're late bloomers that don't start to flower until August. It's best to sow cosmos seeds as soon as the soil is able to be worked.
Torenia is one of the few annuals that tolerate shade. Also called "bluewings" or "wishbone flowers," torenias are bluish-purple and are often grown in hanging baskets. This annual contains two stamens shaped as wishbones that are easily pulled apart. They can be started indoors or planted in early spring. Torenias do best in aerated, well-drained soil and should never be overwatered.
Impatiens, which are native plants of East Africa, are shade-loving annuals that come in both single and double form. Also known as "busy Lizzies," impatiens make exceptional window or container plants. They receive their name from the root Latin word meaning "impatient." Because sometimes their seedpods are sensitive, bursting open from just a light touch, they're impatient to open. Originally impatiens only produced red-brick-colored flowers; but now they're available in various hues ranging from white to salmon and bright shades of orange, rose and bi-colors.