Dahlias are hugely varietal flowers, with little starburst blooms to plate sized flowers in every hue imaginable. Dahlias are relatively sturdy plants if grown in the right lighting, heat, and soil. Dahlias need to be kept weed free. Use organic mulch around the plants to prevent weeds and conserve moisture. Pinch back the terminal buds when the plant is 15" tall to enforce good branching and structure and increase budding. Provide plenty of water to your plants. Water plants deeply once or twice per week.