Most elephantâs ears are perennials and will come back every summer in the Lower, Coastal, and Tropical South. Some are perennials in the lower part of the Middle South.
Dahlias are available in different heights, dwarf dahlias are normally 12 to 18, and the taller dahlias grow 5' to 6'.Dahlias up to 2 ft.ahlias are available in different heights, dwarf dahlias are normally 12 to 18, and the taller dahlias grow 5' to 6'. Dahlias up to 2 ft.
Growing Requirements of Dahlia Plants. Dahlias are summer blooming tubers that are generally only hardy in USDA zones 7-11. In the majority of the country, Dahlias must be planted each spring. and then cut back and dug each fall after the first killing frost. Dahlia plants grow and bloom best in full sun. Dahlias tolerate most soil types, but prefer a sandy, well drained, slightly acidic soil with a pH of 6.2- 6.5.