Plant Luminary® Ultraviolet Tall Garden Phlox in well-drained, fertile soil with full sun exposure. Space plants 18-24 inches apart. Water regularly, keeping the soil consistently moist but not waterlogged. Fertilize with a balanced, slow-release fertilizer in early spring. Deadhead spent blooms to encourage continuous flowering. Divide clumps every 3-4 years in early spring or fall to maintain vigor. Protect from powdery mildew by ensuring good air circulation and avoiding overhead watering.