Good air circulation necessary to prevent powdery mildew. Trim old flower heads after blooming to encourage further buds
David likes a position of full sun and remember to water moderately. Keep in mind when planting that David is thought of as very hardy, so this plant will tend to survive through freezing conditions. David requires a loamy and clay soil with a ph of 6.1 - 7.8 - it grows best in weakly acidic soil to weakly alkaline soil.Easiest from offsets in the spring or division of a mature clump in the spring or autumn
Choose a sunny spot with evenly moist soil, and place at the middle to the back of the border. The stems are tall but relatively self supporting.
Ensure that temperatures are mild and all chance of frost has passed before planting out, as David is a very hardy plant.Very large flowers on tall sturdy stems, last well in a vase
Expect harvests to start to occur in late summer.