The Roque Starburst Dahlia captivates gardeners with its striking beauty and unique floral structure, making it a popular choice for any garden space. This sought-after flower offers an exceptional display, transforming garden beds into vibrant showcases. Cultivating this dahlia variety successfully provides a rewarding experience.
Defining Roque Starburst Dahlia
The Roque Starburst Dahlia features a distinctive semi-cactus form with massive blooms, typically measuring 6 to over 10 inches in diameter. Its captivating petals are often silvery white with hints of blush or lavender, sometimes featuring a subtle latte-colored center. This unique coloration and radiating, pointed petals create the signature “starburst” effect. Standing 4 to 5 feet tall, the plant is vigorous and productive, ensuring a generous display of blooms throughout the growing season.
Planting and Site Selection
Successful cultivation of the Roque Starburst Dahlia begins with proper planting and site selection. These dahlias thrive in full sun, requiring at least six to eight hours of direct sunlight daily. Well-draining soil is a requirement for healthy growth, as tubers are susceptible to rot in waterlogged conditions. Enriching the planting site with compost improves soil structure and fertility, providing an ideal environment for establishment.
Planting should occur in spring, after all danger of frost has passed and the soil has warmed. Tubers should be placed in deep holes with the “eye” facing upwards for new growth. Spacing is important, with individual tubers planted 12 to 18 inches apart to allow for adequate air circulation and growth.
Ongoing Cultivation and Care
Once established, Roque Starburst Dahlias require consistent attention. Regular watering is important, especially during dry periods, to ensure plants remain hydrated. These large plants benefit from appropriate fertilization throughout the growing season to support vigorous growth and prolific flowering.
Staking is necessary for these tall dahlias, as their hollow, brittle stems can easily break under the weight of massive flowers or strong winds. Stakes, such as sturdy hardwood or metal, should be placed near the tuber at planting time to avoid damaging the root system later. As the plant grows, tying main stems to the stake every 12 to 18 inches provides ongoing support, preventing breakage. Regular inspection for common dahlia pests and diseases allows for early intervention, preventing minor issues from escalating.
Encouraging Blooms and Display
To encourage continuous blooming, deadhead spent flowers. These dahlias typically bloom from midsummer until the first hard frost. Removing fading flowers redirects the plant’s energy from seed production back into creating more blossoms.
When cutting blooms for arrangements, harvest them in the early morning or late evening when fully hydrated. Select flowers that are about three-quarters open, as dahlias do not open much further once cut. Cutting the stem above a leaf node encourages the plant to produce new shoots and subsequent blooms. For a longer vase life, typically around 5 days, stems can be given a hot water treatment by searing the ends in 160-180°F water for about an hour before arranging.
Winter Dormancy and Tuber Storage
In colder climates where the ground freezes, prepare Roque Starburst Dahlia tubers for winter dormancy. After the first hard frost blackens the foliage, cut stems back to a few inches above the ground. Allow tubers to remain in the soil for approximately two weeks after this cut; this helps them cure and toughen, reducing storage losses.
Once lifted, gently wash tubers to remove excess soil, then allow them to dry completely for one to two days. This drying process, often called curing, prevents rot during storage. Store tubers in a cool, dark, frost-free location, ideally between 40-50°F (4-10°C), with good air circulation. Packing them in a medium like peat moss, vermiculite, or sawdust helps maintain proper humidity and prevents shriveling, ensuring viability for planting the following spring.