The onosma prefers well-drained, moderately fertile soil and tolerates drought reasonably well. Plant in full sun or partial shade, water thoroughly after planting. Keep soil consistently moist, but not overly saturated. To plant, prepare the soil by removing any debris, place the onosma in the desired location, allowing ample space between plants for air circulation. Water regularly during dry periods. Be aware of the different species' needs within the genus, some may have specific requirements for optimal growth.