The Dahlia ‘Bonesta’ is a striking decorative cultivar celebrated for its unique and playful bi-colored blooms. Each 4 to 6-inch flower presents a creamy white base irregularly streaked with vibrant pink or soft rose, ensuring no two blossoms are exactly alike. This variety grows to a substantial height, typically reaching between 36 and 45 inches over the growing season. The ‘Bonesta’ offers gardeners a continuous display of color from midsummer until the first heavy frost, making it a favorite for cut flower arrangements and garden borders.
Site Preparation and Initial Planting
Successful growth begins with careful attention to the planting location and soil composition. Dahlia ‘Bonesta’ requires a minimum of six to eight hours of direct sunlight each day to produce strong stems and a prolific number of blooms. The soil structure must be well-draining, as the tuberous roots are highly susceptible to rot in consistently soggy conditions.
Amending the planting site with organic matter, such as well-aged compost, helps improve drainage while providing necessary fertility. A slightly acidic to neutral soil pH, ideally ranging from 6.0 to 7.0, is most conducive to healthy dahlia growth. Planting should only occur after the danger of the last spring frost has completely passed.
Planting should be delayed until the soil has consistently reached at least 60°F. Tubers should be placed horizontally in the prepared hole, approximately four to six inches deep, with the crown or eye facing upward. Position each tuber about 18 to 24 inches apart from its neighbor to accommodate the plant’s mature size.
Routine Care Through the Growing Season
Active maintenance during the summer months is necessary to encourage a robust plant that produces numerous flowers. Once planted, avoid watering the soil until you see the first green shoots emerge. After establishment, deep watering once or twice a week is generally sufficient to keep the soil evenly moist, especially during periods of dry weather.
Water at the base of the plant to keep the foliage dry, which minimizes the risk of fungal diseases like powdery mildew. ‘Bonesta’ benefits from a fertilizer program that is low in nitrogen, such as a 5-10-10 ratio, to encourage flower production over excessive leafy growth. Apply this balanced fertilizer monthly, starting about 30 days after the plant begins to grow.
To promote a bushier plant structure with more blooms, the practice of “pinching” is recommended when the plant reaches about 12 inches in height. This involves removing the central growing tip just above a set of leaves, which signals the plant to develop lateral branches. Staking may be required, especially in windy locations or when the plant is heavy with blooms, to prevent the stems from snapping.
Throughout the flowering period, deadheading is necessary to ensure continuous bloom production until the season’s end. Remove spent flowers by cutting the stem back to a pair of healthy leaves or a developing bud. Regularly inspect the foliage for common pests like aphids and spider mites, and ensure good air circulation around the plants as a preventative measure against infestation and disease.
Preparing Tubers for Winter Dormancy
In regions where the ground freezes, dahlia tubers must be lifted and stored to survive the winter. This process is signaled by the first hard frost, which causes the foliage to turn black. After the frost, cut the plant’s stalks back, leaving a stem of about four to six inches attached to the ground.
Carefully dig up the tuber clump, being mindful of the delicate neck where the tuber connects to the stem. Use a garden fork to loosen the soil, working about a foot away from the main stalk to avoid piercing the roots. Allow the tubers to cure in a cool, frost-free, and well-ventilated location for a few days.
After curing, store the tubers in a medium that prevents both desiccation and rot. Materials include slightly moist peat moss, vermiculite, or wood shavings. Store the tubers in a dark, cool environment where temperatures remain above freezing, ideally between 40°F and 50°F, until it is time to replant the following spring.