How to Grow and Care for American Sunset Dahlia
Learn to manage the American Sunset dahlia's full growth cycle. Our guide provides essential techniques for healthy plants and a season of continuous blooms.
The American Sunset dahlia is a favored selection for gardens, recognized for its vibrant, warm-toned blooms. This cultivar is appreciated for its robust growth and the volume of flowers it produces. Its reliable performance and striking appearance make it a popular choice for gardeners looking to add dependable color.
American Sunset Dahlia Characteristics
The American Sunset dahlia is a decorative type with bountiful, double blooms that can reach up to nine centimeters in diameter. The petals showcase a color gradient, blending shades of orange, peach, and red. The reverse side of the petals often displays a deeper carmine or terracotta hue, adding depth to the flower’s appearance. These plants grow to a height of 70 to 120 centimeters with an upright habit, making them a suitable choice for the middle or back of garden borders. The strong, dark-colored stems support the numerous flowers and are excellent for cutting.
Planting and Site Selection
Tubers should be planted in the spring after all danger of frost has passed. Select a site that receives at least six to eight hours of direct sunlight per day for vigorous growth and prolific flowering. A location sheltered from strong winds is also beneficial, as the tall stems can be susceptible to damage.
The soil must be fertile and well-draining to prevent the tubers from rotting. Amending the planting area with organic matter like compost or well-rotted manure will improve soil structure and fertility. When planting, dig a hole four to six inches deep and place the tuber horizontally with the “eye,” or growing point, facing upward.
After placing the tuber, cover it with soil and avoid watering until the first shoots appear to prevent tuber rot. Space the tubers approximately 12 to 18 inches apart to ensure adequate air circulation. Inserting a sturdy stake next to the tuber at planting time provides support later in the season.
Seasonal Care and Maintenance
Once sprouted, water the plants deeply once or twice a week. Applying water at the soil level, rather than overhead, helps reduce the risk of fungal diseases like powdery mildew.
To promote abundant flowers, use a fertilizer with a lower nitrogen content, such as a 5-10-10 or 10-20-20 formulation. Begin fertilizing after the plant is established and continue every few weeks, tapering off in the late summer.
To encourage a bushier plant with more flowering stems, pinch out the central growing tip when the plant is about 12 to 18 inches tall. As the dahlia grows, secure the main stems to the stake placed at planting time. Regularly deadheading, or removing spent flowers, redirects the plant’s energy into producing new blooms and extends the flowering season.
Overwintering Tubers
In climates where winter temperatures drop below freezing, dahlia tubers must be dug up and stored. After the first killing frost has blackened the foliage, cut the stalks down to about four to six inches from the ground. Carefully lift the tuber clump from the soil with a garden fork, digging wide around the plant to avoid damaging the roots.
Gently shake off as much soil as possible from the tubers. Allow the tubers to cure and dry for a few days in a cool, dark, and frost-free location like a garage or shed. This drying period helps prevent rot during storage.
Once cured, place the tubers in a container like a cardboard box or paper bag, covering them with a storage medium such as vermiculite, peat moss, or sand. This material helps maintain a consistent moisture level. Store the container in a cool, dark place where the temperature remains between 40 and 50 degrees Fahrenheit throughout the winter.