Dahlia ‘Thomas Edison’

Dahlia ‘Thomas Edison’ is a remarkable variety that offers both aesthetic appeal and practical versatility. Its stunning purple blooms, robust growth, and adaptability make it a prized choice for gardeners and floral enthusiasts. Whether used to enhance the beauty of a garden or as part of a sophisticated floral arrangement, ‘Thomas Edison’ stands out as a symbol of horticultural excellence and dramatic charm. This dahlia is featured in our top 40 must-see dahlia flowers.

Dahlia ‘Thomas Edison’: An In-depth Look

Dahlia ‘Thomas Edison’ is a distinguished member of the decorative dahlia group, celebrated for its rich, deep purple blooms. This type is characterized by its fully double flowers, lacking a central disc, with broad, flat, or slightly rolled petals arranged in a regular, symmetrical pattern. It is also classified as a dinnerplate dahlia due to its impressively large flowers.

Native: Dahlias are native to Mexico and Central America. This cultivar results from extensive breeding and does not occur naturally in the wild.

Plant Type and Habit: This dahlia is a tuberous-rooted perennial with a bushy, upright growth habit. This variety is known for its strength and vigor, providing a reliable and striking display in garden settings.

Size: It generally reaches about 36-48 inches in height (90-120 cm) and spreads around 18-24 inches (30-60 cm), depending on growing conditions.

Flowers: The flowers of ‘Thomas Edison’ are a key highlight, with their luxurious deep purple hue. The fully double blooms are large, typically measuring 8 inches (20 cm) in diameter. The petals have a velvety texture, and their rich color can appear almost luminous in sunlight, adding a dramatic flair to any garden or bouquet.

Bloom Time: Blooming from mid-summer until the first frost it provides long-lasting color in the garden.

Foliage: The foliage is typical of dahlias, with dark green leaves that provide a lush backdrop for the bright flowers.

Uses: Thomas Edison’ is highly versatile in its application. It is a favorite for cut flower arrangements due to its striking color and large size. In the garden, it serves as an excellent choice for creating a focal point in borders or as part of mixed plantings. The plant’s height and dramatic blooms also make it suitable for background plantings in larger garden designs.

Hardiness: Dahlias are hardy in USDA zones 8-11. In colder zones, tubers need to be lifted and stored over winter.

Toxicity: Dahlias are toxic to dogs, cats, and horses. Their ingestion can lead to gastrointestinal upset and other health issues in pets and livestock.

Wildlife: The flowers attract pollinators such as bees and butterflies.

Deer and Rabbit: Dahlias are somewhat resistant to deer and rabbits but may still be vulnerable to browsing.

Invasiveness: Not invasive; dahlias grow from tubers and do not spread aggressively.

Dahlia Growing Tips

Light: Dahlias love the sun, so choose a location with at least six to eight hours of direct sunlight daily.

Soil: Dahlias prefer well-drained, loamy soil. They don’t tolerate water-logged conditions, so if your soil is heavy clay, consider amending it with compost or peat moss to improve drainage.

Planting Time: Dahlias are usually planted in the spring after the risk of frost has passed and the soil has warmed up.

Planting Depth: Dahlia tubers should be planted about 4 to 6 inches (10-15 cm) deep, with the “eye” (the small bump from where the stem will grow) facing upward.

Watering: Dahlias like consistent moisture. Water them deeply a couple of times a week, more often if your area is experiencing a drought. Avoid overhead watering to reduce the risk of fungal diseases.

Fertilizing: Dahlias respond well to low-nitrogen fertilizers, such as a 5-10-10 or 10-20-20. Too much nitrogen can lead to lush, leafy growth and fewer flowers.

Deadheading: Regularly removing the spent flowers (deadheading) will keep your dahlias producing more blooms.

Overwintering: In colder climates (zones 7 and below), you’ll need to dig up and store the tubers indoors over the winter.

Pests and Diseases: Dahlias are generally relatively disease and pest-resistant, but there are a few common issues to watch out such as aphids, botrytis blight, earwigs, powdery mildew, slugs and snails, spider mites, and thrips.