Planting instructions: Plant Dahlias in well-drained soil in a sunny location. Supply ample moisture and fertilizer during the growing season. When the plant reaches 1-1/2' in height, trim entire plant to 1'. In about two weeks trim the plant again back to about 1-1/2'. This will encourage your Dahlia to produce an abundance of flowers. Remove all spent flowers. These tuberous roots must be lifted from the ground in zones 7 and lower.