Flowering plants that come back every year without replanting are called perennials. There are many to choose from for planting in the southern United States, but native perennials are the best choice because they usually have low maintenance requirements.
Salvia Greggii, or Autumn Sage, is an evergreen shrub in the southern United States that produces several cycles of blooms during the growing season, as long as the dead blooms are trimmed off the plant. It is a very popular hummingbird and butterfly attracting plant and is useful in dry gardens that only get normal rainfall amounts.
Tansy (Tanacetum vulgare) is a perennial herb that produces umbrella-shaped, yellow flowers on long stems in mid-summer. The fern-like foliage has a pungent smell when crushed and is known to repel bad insects. However, the flowers attract beneficial insects to the garden. Tansy grows throughout the United States and Canada.
Camellias (Camelia japonica) are an evergreen shrub with thick glossy leaves that blooms every winter in the southern United States. It is a durable shrub, once established, and has rose-like blooms of red, pink or white depending on the variety. It grows well on the north or east side of a building or under a shade tree where few plants will grow due to low light conditions.
Azaleas (Rhododendron maximum) are shrubs that bloom in early spring and grow in the southern United States. They grow best in deep, moist, acidic soil. Azaleas can be pruned back by one-fourth right after the bloom period to keep them in shape. There are now improved varieties of azaleas that bloom several times during the growing season. The azalea is a shrub that will grow in the shade of a tree that loses its leaves in the winter.
Lantana (Lantana camara) is a perennial, flowering plant attractive to hummingbirds and butterflies. It is native to the southern United States. There are at least 150 varieties available. A few varieties grow to large shrubs, while others are low-growing ground covers. Some varieties of lantana have a neat mounding habit and others produce trailing branches that make them appropriate for hanging baskets.