Florida incorporates the USDA hardiness zones of 8b to 10b. These areas are known for high humidity, top heat conditions, and dry sandy soils. The tough plants for Florida gardens are going to be those that can take sandy soils and the drought like conditions. These drought tolerant plants are all for the hardiness zones found in Florida.
Thryallis (Galphimia glauca) is from the malpighia family. It is an evergreen shrub that is easy to grow and drought tolerant. It gets to 6 feet tall and nearly as wide. Leaves are light green, 1 to 2 inches long, and oblong. Flowers are yellow, under an inch long, and in clusters summer and fall. Seed capsules come after the flowers. Grow in well drained soil in bright sunlight. Propagate by summer cuttings or by seed.
Sago palm (Cycas revoluta), is from the cycad family. It is an evergreen, drought-tolerant perennial palm that is good for containers, indoor use, and shady spots. It can get 10 to 12 feet tall with dark green leaves 4 to 5 feet long. Yellow cones are 12 to 18 inches and orange seeds are 1 1/2 inches wide. Grow sago palm in sandy soils that are fast draining. Propagate via seed.
Spotted horsemint (Monarda punctata), is from the mint family. It is a fast growing drought tolerant plant that attracts butterflies and hummingbirds. It will get 3 to 4 feet tall with hairy leaves 1 to 3 inches long. Flowers are tiny. Grow spotted horsemint full sun. Propagate via seed or clump division.
Coontie (Zamia pumila), is from the coontie family. It is an evergreen and easy growing perennial that is drought tolerant and good for containers and shade. It will get 3 feet tall with 3 feet long dark green leaves. Grow in full sun or shade. When dry, water regularly. It can't grow on beaches but will tolerate salt drift. Propagate via seed.
Cassava (Manihot esculenta), is from the spurge family. It is a drought tolerant perennial. It can get 20 feet tall if frost free or 10 feet tall if regrown. Leaves are dark green on long leaf stems up to 24 inches. Grow cassava in poor soils in full morning sun and partial shade in the afternoon. Propagate via stem cuttings.