Heat Tolerant Annuals
Hot Sun annuals thrive when they receive a fair amount of direct sun each day.
Cannas Flower
These feature stalks rising in the center of fleshy succulent leaves, bear large flowers. Foliage may be green, bronze, or purplish in hue. Cannas need full sun and grow best in a deep, rich, moist but well-drained soil. For earliest bloom, start in pots indoors. Remove spent flower heads for more prolific bloom. In fall after the first light frost, cut back stems to 6 inches, dig roots with soil attached, and store in a cool, frost-free place. While in storage, water sparingly.
Cockscomb/ Celosia
Cockscomb/Celosia feature large flower clusters on top of green or reddish leaves. Colors include yellow, gold, red, pink, orange, and wine. Velvety crested celosia (cockscomb) are rippled, whereas other varieties of celosia are shaped like plumes or spikes. Heights range from 6 to 36 inches; flower size is not determined by height. Grow in rich to average, well-drained soil in full sun.
Cosmo
Cosmo flowers form a lacy, open plant with flowers three to four inches in diameter. These daisy-look-alikes come in pink, red, white, and lavender with a contrasting yellow center. Cosmos grow best in full sun.
Dusty Miller
Dusty miller prefers full sun and ordinary, well-drained soil, though they will grow in lightly shaded areas, too, brightening them with their silver color
Foxgloves
For more blooms on shorter stems, cut the central spike most of the way down before the flowers are fully formed. You'll force growth of many side shoots with flowers on them all. Deadhead plants after they flower, but allow at least a few flowers to ripen fully into tan pods full of brown seeds, and sprinkle the seeds onto cultivated ground where you would like more foxgloves.
Gazania
Gazania grows in rosette form with notched leaves. Flowers rise 8 to 12 inches on short stems. They're white, pink, bronze, red, yellow, and orange with banded markings. Flowers close on cloudy days. Gazanias prefer full sun and moderately fertile but well-drained soil. They don't like heavy soil in hot, humid climates.
Geraniums
Geraniums are upright bushes covered with red, pink, salmon, white, rose, cherry-red, or bicolored flowers on long stems held above the plant. Flower clusters (umbels) contain many individual flowers and give a burst of color. They prefer full sun and moderate to rich, well-drained, moist soil. Geraniums must be dead-headed.
Lantana
Lantana are woody shrubs with large, rough leaves. They grow about three feet tall and equally wide over a summer. Lantanas need full sun and hot weather-and actually poor soil-to give their best performance. Space the plants about 18 inches apart.
Marguerite Daisy Butterfly
A profusion of golden-yellow, daisy-like flowers are produced over the delicate foliage of this plant from May to September. Though the individual flowers are medium, they are produced in large quantities.
Marigold
Marigold can be tall plants, growing up to 36 inches high, though breeding has produced shorter heights. They have large, fully double flowers in yellow, gold, and orange. French marigolds (T. patula) are bushier and more compact with smaller flowers. Triploids, a cross between French and American marigolds, resemble French marigolds but have larger flowers. Marigolds grow best in full sun with moist, well-drained soil, though they will tolerate drier conditions.
Melampodium
Melampodium will form a vigorous, bushy plant 10 to 15 inches high, and about as wide, in the garden. The flowers are small, up to an inch in diameter. Melampodium needs full sun. An average but well-drained soil is satisfactory. Plants should not be allowed to dry out.
Nasturtium
Nasturtium are vigorous and can grow as either vine like or compact bushy plants. The leaves are nearly round, and the flowers are bright oranges and yellows with long spurs behind them. Nasturtiums need full sun in a dry, sandy, well-drained soil. They're at their best in regions with cool, dry summers, though they will grow elsewhere, too. Bushy types get viny or stringy if they have too little sun.
Petunias
Petunias are divided into two types: multifloras and grandifloras. Each has single and double forms, with grandiflora petunias being larger (though new hybrids have blurred this distinction). Singles are more weatherproof than doubles. Well-drained soil in full sun suits petunias best. To promote more branching and increased bloom, shear plants back halfway in midsummer. And we do mean give them a serious haircut!
Plume Celosia
Plume celosia offers large flower clusters on top of green or reddish leaves. Colors include yellow, gold, red, pink, orange, and wine. Velvety crested types (cockscomb) are rippled, whereas others are shaped like plumes or spikes. Heights range from 6 to 36 inches; flower size is not determined by height. Grow in rich to average well-drained soil in full sun.
Portulaca Moss
Portulaca Moss roses grow nearly flat -- a mat of fleshy leaves with stems topped by flowers. Newer varieties are available in a myriad of jewel-like colors. Full sun, sandy soil, and good drainage are musts for portulaca.
Salvia
Depending upon variety, salvia will grow from eight inches to three feet tall. The spikes of flowers are composed of bright bracts with flowers in the center of each. They are either the same color or contrasting. Salvia is a good dual-purpose plant that will perform dutifully in full sun or partial shade. It needs average soil and continuous moisture to perform its best.
Snapdragons
Snapdragons uniformly bear a whorl of flowers atop slender stalks. The best known are ones with snappable flowers, but others have open-faced flowers including double forms. Colors include white, yellow, burgundy, red, pink, orange, and bronze. Plant in rich, well-drained soil with plenty of organic matter. Grow in full sun. Pinch tips of young plants to encourage branching. For cool season bloom, plant snapdragons in September.
Statice
Statice features upright sprays of small flowers enclosed in papery calyces, which last for days as a freshly cut flower and for months when dried. They come in bright or pastel shades. Provide full sun and well-drained soil of moderate fertility. Cut the flowers when blooms are at least three-quarters open. Air dry them upside down in the dark.
Sweet Alyssum
Sweet alyssum grows only a few inches high but spreads as much as a foot in diameter. The tiny flowers are closely packed around small racemes that grow upward. Although white is the most planted color, colors in the pink family are also available. Sweet alyssum grows best in full sun in cool weather, but it will tolerate partial shade. Sweet alyssum will reseed vigorously.
Verbena
Verbena. The trailing plant varieties may reach 18 inches in diameter, while the mounding types will grow to about a foot high and wide. The flowers bloom in clusters and come in strong and pastel shades. Verbenas prefer well-drained, sandy soil with good fertility.
Zinnias
Zinnias flowers come in almost every color except blue and in many textures. Zinnias need full sun and rich, fertile soil.