Dianthus Sweet Scarlet Seedling Tray

Grow Dianthus Sweet Scarlet in full sun to high light with well-drained soil or media. Target a soil pH around 5.8–6.5 and avoid keeping the crop overly wet, especially around the roots. Use a steady nitrate-based fertilizer program at about 175–225 ppm nitrogen once plants are established, while keeping phosphorus on the lower side. Good calcium levels are important for dianthus, so a calcium-based feed such as 15-5-15 can be a solid choice.

Red flowers bloom from spring through fall. This plant has best flowering results in high-light conditions. These conditions, combined with high heat, may result in shorter stems.

Pinching is optional and depends on how the grower wants to finish the crop. For standard cut-flower production, many growers do not pinch because they want strong, straight stems. If a fuller plant or more branching is desired, a light pinch can be used, but it may add time to the crop and reduce uniformity.

Space plants at approximately 4–6 per square foot for cut-flower production to promote airflow and maximize yield. For landscape use, plant 10–14 inches apart.

Scout regularly for aphids, thrips, whiteflies, and spider mites. Thrips become the primary concern once buds develop because they can damage flowers before harvest.

Monitor for rust, Botrytis, Fusarium, Pythium, Rhizoctonia, and powdery mildew. Good airflow is essential because flower heads can trap moisture. Avoid late-day irrigation and prevent plants from remaining wet overnight. Outdoor plantings may benefit from a preventative rust program.

We recommend planting one plug per four inch pot and three to five plugs per ten inch pot.