Dahlias come in a stunning range of shapes, sizes and colors. Cactus dahlia varieties are a particularly striking group of plants. Each cactus dahlia is a double flower and is characterized by petals that curve in along their lengths. The semi-cactus dahlia is similar. Each petal curves in about halfway down its length, while the petals of the cactus varieties are curved for the entire length.
Both these dahlia plant types add impact and drama, while holding their own in bad weather. The half-effort gives a semi-cactus dahlia flower a fluffier look. Look for cactus dahlia bulbs (or tubers) in any of the varieties listed below, and add a dramatic new flower to your beds or containers.
Choosing the Best Cactus Dahlia Varieties
If you want to try this striking flower in your garden, there are several types of cactus dahlia and semi-cactus dahlia to choose from. Most semi- and cactus dahlia varieties are tall, rising to over three feet (90cm).
In addition to their interesting blooms, they are useful for being sturdy and stand up well to bad weather. So while you might have to protect other dahlias from falling, these types don’t usually require staking. Here are a few of the most note-worthy cactus dahlias to try.
1. Chat Noir
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French for ‘black cat’, this is one of the most striking black dahlia varieties you can grow. It is a deep black-red that can appear fully black towards the center of the flower. It flowers from June until October, although it can last as late as the first frost.
2. Frigoulet
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For a dramatic double color, these gorgeous bloomers convey a real ‘raspberry ripple’ effect, with rich red petals and white tips. Dynamic in the fronts of borders, it blooms from July until well into the fall and has impressive longevity as a cut flower.
3. Karma Bon Bini
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Also double colored, this variety has fiery red-orange petals and sunshine yellow centers. Looking like a solidified explosion, these flowers set beds and borders alight from midsummer until fall. Individual flower heads can reach four inches in diameter.
4. Henriette
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For a gentler, softer garden palate, try this semi-cactus dahlia. Rippled petals present with smoky blush-orange hues and butter-cream centers. Rising on strong, elongated stems, it flowers from July until the first frost and only gets better with age.
5. My Love
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Taking on the appearance of spiked snowballs, this is a gorgeous dahlia choice if you are looking for the best white flowers to grow. This brilliant white cactus-type fades to a lemon yellow and lime center, and it blooms from July until October.
6. Karma Corona
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Unique in tone and texture, this pretty semi-cactus fuses appealing tones of mango and peach along its petal spikes. Soft melon-pink spikes fade to chewy yellow centers. Massive flower heads will continue to develop from July until first frost.
7. Karma Pink Corona
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A gorgeous companion plant to Karma Corona, so grow this alongside its peachy relative to create the perfect partnership of pinks and yellows. With violet pink spikes blending to bubblegum centers, this dahlia type also flowers from July to October.
Frequently Asked Questions
How Do I Best Care for Cactus Dahlia Varieties?
Most dahlia types have similar care needs, and cactus dahlia care follows the same principles. Plant tubers in spring to get blooms from summer into fall. Give your dahlias full sun and rich, well-drained soil.
Most dahlias do best with some wind protection, though cactus varieties are sturdier. Remember to deadhead flowers as they fade. If you live in a cold climate, you’ll need to dig up the tubers to overwinter indoors if you want to save them for next year.
When and How Often Should I Water Cactus Dahlias?
Once you have planted dahlia tubers, wait until you see some green emerging from the soil before you water. Watering too early can cause rot. Water dahlias deeply a few times a week and provide a low-nitrogen fertilizer through the growing season.
