Dahlias are stunning flowers that brighten gardens with vibrant yellow, white, and pink blooms throughout the warmer months. While they are relatively easy to grow, gardening experts caution against planting dahlias in certain spots that can hinder their growth and flowering.
1.Small Containers
Dahlias can thrive in pots, but only if the containers are large enough. According to Kate Walz, horticulturist and floral designer, pots smaller than 12 inches in diameter restrict root growth, resulting in weak plants and fewer blooms. Mary Turner, master gardener and flower farm owner, recommends pots at least 15 inches wide to support healthy, top-heavy dahlias.
2.Soggy, Poorly Drained Soil
Dahlias prefer loose, well-drained soil. Planting them in soggy or clay-heavy soil invites tuber rot due to excess moisture. Turner advises creating raised beds if your garden has areas with standing water to keep dahlias healthy and flourishing.
3.Hot, Humid Conditions
Though dahlias love full sun, extreme heat and humidity can stress the plants. Walz explains that temperatures above 90°F during the day and warm nights prevent dahlias from resting and producing flowers. Cooler nights in early fall, especially in Zone 7 gardens, encourage prolific blooming.
4.Shady Locations
Dahlias need at least six to eight hours of direct sunlight daily. In shaded or densely wooded areas, they become leggy and rarely flower because they lack the sunlight necessary for energy-intensive bloom production.
5.Crowded Plantings
Dahlias require space to grow strong and resist pests and diseases. Turner recommends spacing plants at least 18 inches apart to reduce stress and encourage healthy flowering.
By avoiding these common planting mistakes, gardeners can enjoy the full beauty of dahlias, ensuring their gardens burst with colorful, show-stopping flowers all season long.
