The ‘Santa Claus’ Dahlia offers a festive display, making it a desirable addition to many gardens. This guide provides detailed insights into cultivating and maintaining these striking flowers.
Distinctive Features of Santa Claus Dahlia
The ‘Santa Claus’ Dahlia is known for its unique aesthetic, characterized by a striking red and white color combination. Its petals display deep red at the center and crisp white edges, creating an eye-catching appearance. This distinct variegation is reminiscent of candy canes, giving the dahlia its common name.
This variety produces medium-sized informal decorative blooms, 4 to 6 inches across. The petals curve back and may twist slightly, creating a feathery look. Reaching 36 to 54 inches in height, the ‘Santa Claus’ Dahlia stands out in the garden.
Cultivating Santa Claus Dahlias
Site Selection and Soil
These plants thrive in full sun, requiring 6 to 8 hours of direct sunlight daily for robust growth and abundant blooms. In regions with intense afternoon heat, partial afternoon shade can prevent scorching.
‘Santa Claus’ Dahlias prefer rich, well-draining soil with good organic matter. Good drainage is crucial as tubers are susceptible to rot in overly wet conditions. Amend heavy clay or sandy soil with compost or peat moss to a depth of 10 inches to improve drainage and nutrient content.
Planting Tubers
Dahlia tubers should be planted in spring after all danger of frost has passed, typically between mid-April and mid-May. Planting too early in cold, damp soil can lead to tuber rot.
Dig a hole 4 to 6 inches deep, laying the tuber horizontally with the “eye” or sprout facing upwards. Space individual tubers 12 to 18 inches apart. Backfill the hole with a few inches of soil, ensuring the tuber is completely covered.
Care and Maintenance for Thriving Blooms
Watering
After initial planting, avoid watering tubers until the first shoots emerge. Excess moisture before sprouts appear can lead to tuber rot, especially in cooler soils. Once plants have sprouted and are 3 to 8 inches tall, begin deep and consistent watering.
Dahlias require deep watering two to three times per week, moistening the soil to 8 to 10 inches deep. Frequency may increase during hot, dry periods or for container plants, which often need daily watering. Consistent moisture encourages strong root development and continuous blooming.
Fertilizing
‘Santa Claus’ Dahlias benefit from a balanced fertilization regimen. Incorporate organic matter like compost or well-rotted manure into the soil before planting for initial nutrients. Once plants are established and show substantial leaf growth, begin applying fertilizer.
Dahlias prefer a low-nitrogen fertilizer; too much nitrogen promotes lush foliage at the expense of flowers. A 5-10-10 or similar ratio fertilizer, high in phosphorus and potassium, is recommended. Apply fertilizer every 3 to 4 weeks during the growing season, or every 2 to 3 weeks for container-grown dahlias, to support continuous blooming.
Staking and Support
Due to their 3 to 4-foot height, ‘Santa Claus’ Dahlias often require staking to prevent toppling, especially in windy conditions or after heavy rain. Install support during planting to avoid damaging tubers or roots later. Use sturdy wooden or metal stakes, or tomato cages.
For individual plants, drive a stake firmly into the ground next to where the tuber is planted. As the dahlia grows, gently tie the main stem to the stake using soft ties or twine, ensuring the ties are not too tight to allow for stem expansion. For multiple plants, a corral system using posts and sturdy twine can provide collective support.
Deadheading
Deadheading, the practice of removing spent or fading blooms, encourages the plant to redirect energy from seed production to developing more flowers, extending the blooming period. Regular deadheading ensures a continuous display of vibrant blooms from mid-summer until the first frost.
To deadhead effectively, locate a faded flower and follow its stem down to the nearest leaf node or main stem, then make a clean cut above it. It is important to distinguish between spent blooms, which may appear pointed or squishy, and new, rounder buds that are still developing. Weekly deadheading is usually sufficient, but during peak bloom, you may need to deadhead every few days.
Winterizing and Storage
In colder climates (USDA Zones 7 and below), ‘Santa Claus’ Dahlia tubers are not winter hardy and must be dug up and stored indoors. The ideal time is after the first hard frost, which signals dormancy. Foliage will typically turn black, indicating it’s time to lift them.
Carefully dig up the entire clump of tubers, being mindful not to damage them. Gently shake off excess soil, then allow the tubers to dry or “cure” for several days to a week in a cool, dry place with good air circulation, away from direct sunlight. Once cured, store the tubers in a cool, dark, and frost-free location, ideally between 40-50°F (5-10°C), with moderate humidity. They can be placed in cardboard boxes, plastic bins, or paper bags, often layered with peat moss, vermiculite, or wood shavings to help maintain consistent moisture and prevent shriveling or rot. Periodically check on the tubers throughout winter, removing any that show signs of rot or shriveling.
Addressing Common Dahlia Issues
‘Santa Claus’ Dahlias can encounter common garden pests and diseases. Aphids are small, pear-shaped insects that suck plant sap, leading to yellowed, curled leaves and stunted growth. They can also transmit plant viruses. Thrips are tiny, slender insects that cause stippled, distorted leaves and deformed flowers. Slugs and snails are problematic for young dahlia shoots, causing holes in leaves and stems.
Spider mites, which thrive in hot, dry conditions, cause foliage to become yellow and mottled, sometimes leading to wilting. Earwigs can chew on buds and flowers, causing damage. For pests, physical removal, insecticidal soaps, or organic repellents are effective. Consistent watering can also deter thrips and spider mites.
Regarding diseases, powdery mildew appears as a white, powdery coating on leaves and stems, often in humid conditions. Viral diseases, such as Dahlia Mosaic Virus, can cause mottling, distortion, and stunted growth. While there’s no cure for viral infections, managing sap-sucking insects like aphids, which can transmit viruses, helps prevent their spread. Ensuring good air circulation and avoiding overhead watering can help reduce the incidence of fungal diseases like powdery mildew.