The ‘Frank Holmes’ dahlia is a popular cultivar known for its perfectly formed, globe-shaped blooms. Classified as a pompon dahlia, it produces dense, small flowers, typically measuring between one and two inches across. The color is a vivid violet or lilac-pink, offering a striking contrast against the dark green foliage. This vigorous plant typically reaches a height of three to four feet, establishing itself as a robust centerpiece in the garden.
Getting Started: Site Selection and Planting
Selecting the proper location is the first step in ensuring a healthy and productive growing season for the ‘Frank Holmes’ dahlia. This plant requires a minimum of six to eight hours of direct sunlight each day to support its robust growth and prolific blooming. Full sun promotes strong stems and prevents the plants from becoming weak and spindly.
The tall, bushy nature of this cultivar requires protection from strong winds to prevent mechanical damage to the stems and blooms. Dahlias thrive best in soil that is rich in organic matter and offers excellent drainage. Before planting, amend the area with compost or aged manure to improve soil structure, aiming for a slightly acidic to neutral pH level around 6.5.
Planting should occur after all danger of the last spring frost has passed and the soil temperature has warmed sufficiently. Place the tubers horizontally into the prepared ground, positioning the ‘eye’ or sprout upward, and cover them with four to six inches of soil. Space each tuber approximately two feet apart to allow for proper air circulation and root development. After planting, avoid watering the soil immediately, as excess moisture before the sprouts emerge can encourage the tubers to rot.
Essential Care During the Growing Season
Once the dahlia plant has established itself above ground, a careful watering and feeding regimen becomes necessary for continuous flower production. When the plants are actively growing, they require deep watering, ensuring the soil is soaked thoroughly but allowed to dry slightly between applications. Watering frequency will increase significantly during periods of high heat or heavy blooming, which prevents stress and supports its dense foliage.
Fertilization is a delicate balance, as too much nitrogen will promote lush green growth at the expense of flower development. Apply a low-nitrogen fertilizer with higher concentrations of phosphorus and potassium, such as a 5-10-10 or 10-20-20 NPK ratio. Begin the feeding schedule about 30 days after planting, repeating the application every three to four weeks throughout the growing season.
Providing physical support is necessary for this cultivar, as the four-foot stems can easily snap under the weight of the blooms or during strong winds. Place a sturdy stake near the tuber at the time of planting to avoid later root damage, loosely tying the main stem to the stake as the plant grows taller. To encourage a bushier plant with more blooms, pinch off the central growing tip once the plant reaches about 12 inches in height.
Consistent deadheading of spent flowers is important to redirect the plant’s energy from seed production back into creating new buds. Monitor for common garden pests, such as slugs and earwigs, which are attracted to the tender new growth. Checking the foliage frequently for early signs of issues like powdery mildew allows for swift treatment, maintaining the plant’s overall health and vigor.
Winter Preparation and Tubers Storage
For gardeners in colder climates, the ‘Frank Holmes’ tubers must be lifted and stored to protect them from freezing temperatures. The process begins after the first hard frost of autumn blackens the foliage, signaling that the plant has entered dormancy. Cut the stems back to about four to six inches above the soil line.
Use a garden fork to loosen the soil in a wide circle around the stem, lifting the tuber clump without damaging the fragile neck or skin. After lifting, allow the clumps to air-dry in a cool, sheltered location for several days to cure the skin and reduce the risk of rot during storage. This curing period requires good air circulation.
The ideal storage environment is a cool, dark place with a consistent temperature range of 38 to 50 degrees Fahrenheit. Tubers should be stored in a medium like peat moss, vermiculite, or dry sawdust, which helps to regulate humidity and prevent moisture loss. Check the tubers periodically throughout the winter; if they appear shriveled, misting the storage medium slightly can prevent dehydration, or if they show signs of rot, remove the affected tubers and reduce the humidity.