Annual plants for Atlanta come in two types. There are annual plants that grow as perennials in warmer areas to the south and annual plants that grow as annuals no matter where they are. Atlanta is in USDA Hardiness Zone 8, where winter temperatures can get as low as 10 degrees. Watch for the danger of frost to be over in the spring before planting annual seeds outdoors. Start the seeds indoors and plant the seedlings outside when you are sure the frost danger is past, to ensure a good flower crop.
Love-lies-bleeding (Amaranthus caudatus) is also known as tassel flower, Inca wheat, velvet flower and amaranth.The plant grows from 3 to 5 feet tall, 18 to 30 inches wide and produces pale-green leaves and small purple-crimson flowers that grow in tassel-like clusters up to 2 feet long.
The plant may live for more than one year if it does not encounter any frost, otherwise it is a normal annual. Plant love-lies-bleeding in full sun and a dry, un-fertilized soil. In the colder zones, start the plant indoors and plant after the danger of frost has passed.
Orange cosmos (Cosmos sulphureus) grows from 1 to 7 feet tall, producing green feathery leaves and yellow or orange bowl-shaped flowers measuring from 2 to 3 inches in diameter. Plant orange cosmos in full sun and a well-drained, sandy soil. In areas where there is a danger of frost, plant the flower in the spring. In warmer areas, planting can be done in the spring or fall. Orange cosmos will re-seed itself.
Dusty miller (Senecio cineraria) grows up to 2 feet tall with a slightly wider spread. The plant produces silver-gray leaves and mustard-yellow flowers that measure 1 inch across growing in 4-inch wide clusters at the ends of the stems. Plant dusty miller in full sun and a well-drained soil. In mild winters, when it does not get damaged by frost, the plant has a chance of surviving for another summer.
Mexican sunflower (Tithonia rotundiflora) grows from 5 to 6 feet tall and 3 to 4 feet around, producing coarse, fuzzy leaves that measure 4 to 10 inches long and 2 to 4 inches wide. The red or orange flowers resemble a daisy and grow to about 3 inches across. Plant Mexican sunflower in full sun, filtered sun or partial shade and a moist, well-drained soil. The plant will be killed by a frost, but it re-seeds itself and new plants will grow the next spring.