Red blooms with white tips. Growing Dahlias: All the gardener needs to do is plant the tubers after spring frosts in good garden soil with full sun. It's best to position them against a wall or be ready to stake them, since they are brittle, and must be protected from high winds. (If you've grown perennial Delphiniums, the plant size and growth is similar, but success with Dahlias is much easier.) Keep them free of bugs, well-watered, and well-fertilized as they grow, and your dahlias will begin to set buds by midsummer and be in full bloom, usually during July or August. Then the huge flowers keep coming until frost
