The ‘Tam Tam’ dahlia is a distinctive and popular choice for gardeners seeking to infuse their outdoor spaces with vibrant color and unique texture. Its striking appearance and abundant blooms make it a favored subject in garden design, whether as a focal point in borders or as an eye-catching addition to containers. The appeal of this particular dahlia lies in its consistent display of rich hues, creating a visual spectacle from mid-summer until the first frost. Gardeners often select ‘Tam Tam’ for its ability to produce a profusion of flowers, enhancing any planting scheme with its energetic presence.
Understanding Tam Tam Dahlia
The ‘Tam Tam’ dahlia is classified as a ball dahlia, characterized by its exquisitely formed, fully double blooms. These flowers exhibit a deep burgundy to near-black or reddish-black coloration, presenting a luxurious, satin-like finish. The petals are tightly inrolled, forming a flattened ball shape, typically measuring between 3 to 4 inches wide (7-10 cm). This variety grows to an average height of 2 to 3 feet (60-90 cm) with a spread of 1 to 2 feet (30-60 cm). Its vibrant blooms are beautifully contrasted by dark green, divided foliage, contributing to its overall visual impact.
Planting and Ongoing Care
Successful cultivation of ‘Tam Tam’ dahlias begins with proper site selection. These plants thrive in full sun, requiring a minimum of eight hours of direct sunlight daily to produce the most abundant blooms. A location that offers some shelter from strong winds is also beneficial to protect their upright habit.
Well-draining soil is important, as tubers are prone to rot in overly wet conditions. The ideal soil composition is fertile and humus-rich, with a pH that can be acidic, alkaline, or neutral. Amending the soil with organic matter, such as compost, before planting helps create an optimal growing environment.
Planting should occur after all danger of frost has passed in spring, when soil temperatures consistently reach 55-60°F (13-16°C). Tubers are typically planted 2 to 4 inches (5-10 cm) deep with the “eye,” or growth bud, facing upwards, and spaced approximately 18-24 inches (45-60 cm) apart. Initial watering should be light until sprouts emerge, as excessive moisture can cause tuber rot. Once established, ‘Tam Tam’ dahlias require consistent, deep watering, about three to four times per week, ensuring moisture penetrates 8-10 inches into the soil. Container-grown dahlias may need watering once or twice daily, particularly in hot, dry weather.
Fertilizing supports robust growth and prolific flowering. Dahlias benefit from a low-nitrogen fertilizer, with higher percentages of phosphorus and potassium, such as an NPK ratio of 5-10-10 or 10-20-20. Begin applications about 30 days after planting, repeating every three to four weeks throughout the growing season. For dahlias in containers, fertilize every two to three weeks, as nutrients leach more quickly from pots.
Providing support through staking is often necessary, especially for plants reaching 3 feet or more in height, to prevent stems from breaking due to wind or heavy blooms. Regular deadheading, which involves removing spent flowers, encourages the plant to produce additional blooms, extending the flowering period.
Winter Care and Storage
For gardeners in cooler climates (USDA Hardiness Zones 3-7), ‘Tam Tam’ dahlia tubers need to be lifted and stored for winter. The optimal time to dig tubers is after the first hard frost, when the foliage has turned black, typically waiting one to two weeks following this event. To begin, cut the stems back to about 3-4 inches (7-10 cm) above the ground. Carefully dig around the plant, taking care not to damage the brittle tubers, then gently brush off excess soil. Some gardeners prefer to wash the tubers, while others leave the soil on.
After digging, tubers need to cure or dry for several days to a few weeks in a cool, dry location with good air circulation, out of direct sunlight. This curing process helps prevent rot during storage. Once cured, store the tubers in a dark, frost-free environment where temperatures remain between 38-50°F (4-10°C).
Aim for a relative humidity of 75-95% to prevent shriveling or excessive moisture. Store tubers in cardboard boxes or crates, layered with a medium such as peat moss, vermiculite, or sawdust, ensuring the tubers do not touch each other. Plastic bags or airtight containers are not recommended unless humidity is carefully controlled. Check stored tubers monthly for any signs of rot or shriveling and adjust conditions or remove affected parts as needed.
Addressing Common Challenges
Even with diligent care, ‘Tam Tam’ dahlias can encounter some common issues. Pests such as slugs, earwigs, spider mites, and aphids can target dahlia plants, especially young seedlings. Monitoring plants regularly allows for early detection and simple control methods. Fungal problems, like powdery mildew, may also arise; ensuring good air circulation around plants can help prevent such issues.
Beyond pests and diseases, growth-related challenges can occur. A lack of blooms often indicates insufficient sunlight or an imbalance in fertilization, specifically too much nitrogen which promotes leafy growth over flowers. Leggy growth, where stems become elongated and weak, typically results from inadequate light exposure. This can be managed by ensuring the plant receives full sun or by pinching back the growing tips to encourage bushier growth and more flowering stems. Consistent attention to these factors helps maintain healthy, floriferous ‘Tam Tam’ dahlia plants.