The ‘Grand Finale Dahlia’ is a visually stunning addition to any garden, known for its impressive blooms and vibrant colors. This dahlia variety offers a magnificent presence, transforming garden spaces with its showy appearance.
Understanding Grand Finale Dahlia
The ‘Grand Finale Dahlia’ is a “dinnerplate” variety, known for its large blooms that can reach 10 to 12 inches across. These impressive flowers feature a captivating blend of burgundy and magenta, often with light pink or white tips, providing a grand visual impact. The petals form a semi-cactus classification, giving the blooms a spiky, airy appearance.
This dahlia grows to a height of 36 to 48 inches (3 to 4 feet), making it a prominent feature in garden beds and borders. It produces abundant blooms from summer to the first frost. Robust plants and thick, tall stems support these grandiose blooms effectively.
Planting Grand Finale Dahlia
Planting ‘Grand Finale Dahlia’ tubers should occur in spring, after all danger of frost has passed. These dahlias thrive in full sun, requiring at least six hours of direct sunlight daily for optimal growth and abundant blooms. The ideal soil is rich, porous, and well-draining, yet capable of retaining sufficient moisture.
A soil pH between 6.5 and 7.0 is ideal. If your soil is heavy clay or very sandy, amending it with organic matter like peat moss or well-rotted compost can improve drainage and structure. Plant tubers 3 to 5 inches deep and space them approximately 12 to 16 inches apart for proper air circulation and growth. After planting, water thoroughly to settle the soil, but avoid overwatering until green growth appears.
Ongoing Care for Grand Finale Dahlia
Consistent, deep watering is important, especially during dry periods. Once plants sprout, water at least once per week, increasing frequency during hot, dry spells. Mulching around the base helps retain soil moisture and regulate temperature.
Dahlias are heavy feeders. Use a low-nitrogen fertilizer, often called “bloom food,” with a higher percentage of phosphorus and potassium (e.g., 5-10-10 or 2-15-15). Fertilize approximately 30 days after planting, then repeat applications every three to four weeks throughout the growing season. Due to their height and bloom size, plants benefit from staking or other support to prevent toppling. Deadheading spent flowers regularly encourages more blooms, extending the display.
Winter Care and Tuber Storage
In regions where temperatures drop below freezing, ‘Grand Finale Dahlia’ tubers must be dug up for winter storage. After the first hard frost, which blackens the foliage, cut stems back to about 4 to 6 inches above ground. Carefully dig up the tubers, making sure not to damage them, and gently remove excess soil.
Allow dug tubers to cure for one to two days in a warm, dry place with good air circulation to dry completely before storage. This curing process helps prevent rot. Store cleaned, cured tubers in a cool, dark, frost-free location, ideally at 40 to 50 degrees Fahrenheit (4-10 degrees Celsius) with approximately 75-90% humidity. Common storage mediums include peat moss, vermiculite, or wood shavings, which help maintain humidity and prevent drying. Check tubers periodically throughout winter for signs of rot or shriveling, adjusting conditions as needed.
Troubleshooting Common Dahlia Problems
‘Grand Finale Dahlia’ can encounter common garden pests like aphids, slugs, spider mites, and earwigs. Aphids, thrips, and spider mites can cause distorted leaves and diminished plant vigor; insecticidal soaps or horticultural oils help manage these. Slugs and snails cause irregular holes in foliage and can be deterred with traps or organic repellents.
Fungal diseases like powdery mildew and botrytis (grey mold) can also affect dahlias. Powdery mildew appears as a white, powdery coating on leaves, while botrytis causes buds and flowers to turn dark and develop fuzzy grey mold. Proper air circulation and removing affected plant parts help control these issues. Lack of blooms or poor bloom quality often relates to insufficient sunlight, inadequate watering, or too much nitrogen.