Many dahlias, especially the impressive dinnerplate types, are towering, impactful plants that are perfect for supporting the back of your border. With a wide and colorful variety to choose from, there are almost too many options when it comes to these spectacular blooming beauties. Almost. 

While some of the tall dahlia varieties may overwhelm in other areas of the garden, they are great for creating a colorful and showy backdrop. They’re also excellent for cutting, so you get more than one benefit from planting these in larger numbers. A border of dahlias means a bountiful supply of blooms from summer until the first frost. 

This is a lovely example of a dinnerplate dahlia. The flowers can reach eight inches in diameter, placing them in a category with the largest bloomers. ‘Cafe au Lait’s’ signature trait is its soft, creamy, blush tones that shift with weather and maturity. This is a favorite for weddings and makes a striking presence in the garden. 

‘Thomas Edison’

Tall stems carry blooms like royal velvet jewels.

This tall dinnerplate dahlia variety always makes a statement, wherever you plant it. ‘Thomas Edison’ is a striking, rich purple dahlia with classic form and a towering presence. The decorative blooms are large and an intense, regal violet color. These retain their color beautifully. 

‘Thomas Edison’ is tall and stately, and definitely requires staking. You want those beautiful flowers to stand upright, not fall flat in the background. This is a prolific bloomer, and the flowers have a lot of depth. It’s wonderfully dramatic and captivating. 

‘Emory Paul’

Each flower looks like spun sugar kissed by magenta.

If you want a truly enormous, impressive dahlia for the back of the border, ‘Emory Paul’ has few rivals. It’s difficult to compete with the largest of flowers; these blooms can reach up to a foot in diameter! They are simply massive and make an incredible statement. 

This decorative dahlia has soft, wavy petals in bubblegum pink with a deep magenta heart. it doesn’t produce a ton of them, but with blooms this big, you don’t need it to. They are amazing in floral arrangements, and heavy, so staking is essential. 

‘Kelvin Floodlight’

Giant golden heads that light up cloudy garden days.

When I planted this legend two years ago, it was simply on a whim. I had no idea what I was in for, and man, was I in for a treat! ‘Kelvin Floodlight’ is simply spectacular. This tall dinnerplate dahlia variety has a celebrated history and place in the dahlia hall of fame. 

‘Kelvin Floodlight’ is not the tallest dahlia; the plants grow to about four feet tall, so take that into account. They also don’t produce a ton of flowers, but I promise that they are worth the effort. The giant, ten-inch flowers are butter yellow and live up to their bright and blazing name. 

‘Otto’s Thrill’

Cotton candy pink petals with all the garden drama.

‘Otto’s Thrill’ is the quintessential dahlia for the back border of your cottage garden. It’s an incredibly romantic and impressive cultivar, and a favorite among florists. If you want elegance and drama, plant this dahlia; you won’t be sorry you did.

This informal decorative dinnerplate variety has extra-large blooms in the perfect shade of cotton candy pink. They are large, fluffy, and spectacular. The blooms will take on warmer or cooler tones depending on the weather and amount of light exposure. They are full and luxurious. 

‘Labyrinth’

A riot of color that never repeats itself twice.

‘Labyrinth’ is a stunning and artsy tall dahlia variety. It’s known for its wild, twisting petals and gorgeous blend of sunset tones. It’s a favorite for floral arrangements due to its dramatic flair and subtly shifting beauty. The dinnerplate-sized blooms grow on three to five-foot stems, making it perfect for the back of the border. 

The large, flamboyant flowers are a breathtaking blend of coral, peach, pink, salmon, and apricot, with hints of yellow to warm things up. Not only does each flower have its own unique color combination, but each petal on the flower can vary in shade. No two flowers are the same. 

‘Spartacus’

A showstopper’s bloom, rich and velvety to the core.

‘Spartacus’ is a bold and dynamic dinnerplate dahlia. It’s known for its deep, dramatic color and large, velvety blooms. This flower brings a commanding presence to the garden. It’s terrific for cutting and looks incredible in the back of the border, where it will draw the eye over even the flashiest of neighbors. 

The extra-large blooms are a rich, velvety crimson with burgundy undertones. The stems are tall and sturdy, but you’ll need to stake them as the flowers are large and heavy and will pull them over when they bloom. The blooms occur high up on the plant, making them ideal for this purpose. 

‘Rip City’

Burgundy spheres that stand tall and bloom nonstop.

‘Rip City’ is a dependable favorite of mine. The flowers are not as large as the tall dinnerplate dahlia varieties, but it’s a great producer, and it’s nice and tall. It’s great for the back of the border. The ball-shaped blooms are notorious for their deep, rich, sophisticated burgundy color. They are nearly black in the center, and considered one of the darkest red dahlias. 

I’ve heard some describe ‘Rip City’ as moody and sophisticated, and that is a perfect description. They are great bloomers, too. Reliable and robust, these tall plants do their job exceptionally well. 

‘Dutch Pearl’

Elegant ombre petals that make cutting garden dreams.

This is my first year seeing blooms on my ‘Dutch Pearl’, and it was worth the wait. The luminous coral pink flowers are some of the loveliest in my garden. It’s not a dinnerplate, but the pretty, four-inch flowers grow atop tall stems of about four feet. This plant definitely needs staking, as its stems are thinner than those of some larger varieties. 

‘Dutch Pearl’ features decorative blooms in an ombre of coral to pink, with a nearly purple center. They last longer than most dahlias in a vase, making them excellent for the cutting garden. I highly recommend this vigorous cultivar. 

‘Frizzy Lizzy’

Wild, curly petals give every stem a playful twist.

If you’re looking for bold and whimsical, give ‘Frizzy Lizzy’ a chance to win your heart. This is a spectacular dahlia that looks great in the back of the border, or anywhere else you need a splash of fantastical color and flair. The tall plants require staking to keep them upright, and they make an excellent focal point in the garden. 

‘Frizzy Lizzy’ has bright magenta to purple flowers. They resemble a thistle in color and form, with wildly twisting and curling petals that give them a frizzy look. It’s a fantastic cut flower, and truly makes an incredible focal point wherever you plant it. 

‘Javier G’

Elegant symmetry and deep color—florist favorite for a reason.

‘Javier G’ is a lovely and dramatic red dahlia that always rises to the occasion. The blooms are significant, though not oversized, and flashy in a classic shade of lipstick red. It’s a popular and well-loved choice among exhibition growers and florists. 

This is a tall variety with mid-sized flowers, but staking is still recommended. The flower form is formal and decorative, with elegant, rounded petals in velvety red with a deep, nearly black center. They are wonderfully symmetrical, and I highly recommend these for the background of the cutting garden. 

‘Shadow Cat’

Keeps blooming long past when others give up.

Another gorgeous and dramatic red cultivar, ‘Shadow Cat’, is darker than most and has a mysterious and moody personality. The formal, decorative blooms are medium to large and wonderfully well proportioned. Neat, symmetrical, and cupped, they are lovely in the garden and in floral arrangements. 

This plant is approximately four feet tall and shrubby, rivaling any red rose for attention and elegance. It blooms for a long season, and the color and vigor are at their best when it receives plenty of sunlight. 

‘Swan Lake’

Tall stems hold snowy blooms like little clouds floating.

Our final candidate for the back of the border is ‘Swan Lake.’ This elegant, graceful cultivar earns its reputation with stunning, pure white blooms and a refined form. The formal, decorative form adds to the refinement of the snowy flowers. 

This timeless variety is terrific in the garden. The plants are tall and elegant, and the flowers are a standout, despite their demure form. They are perfect for cutting and popular for weddings. If you want a graceful, pristine backdrop for your borders, this is an ideal selection.