If the charm of traditional English gardens has captured your heart, you’re probably eager to infuse your outdoor space with a similar vintage flair. One key element in achieving this look is incorporating flowers that evoke nostalgia and whimsy. Delphiniums are an excellent choice for adding a touch of elegance and sophistication to your garden borders.
With their diverse range of sizes, from towering giants to compact dwarf varieties, these versatile blooms can thrive in pots, brighten up fence lines, or add a pop of color to your exterior space. As you ponder growing delphiniums, it’s essential to know that they’re not only visually stunning but also attract pollinators like bees and hummingbirds. For those new to cultivating this plant, here are the key takeaways:
What Are Delphiniums?
Delphiniums, a type of perennial plant that belongs to the Ranunculaceae family, also known as the buttercup family, are a popular choice for gardens and floral arrangements. They thrive in USDA Growing Zones 3 to 8 with cooler conditions, but can be grown as biennials or annuals in warmer regions. With over 370 species among the 2,000 annual and perennial plant varieties in this family, delphiniums bring height, color, and visual impact to borders and cut flower arrangements.
While new heat-tolerant varieties are being developed, these plants generally prefer moderate temperatures. The taller types require protection from wind, as they can easily topple over without it.
10 Excellent Delphiniums
While sharing similarities with larkspurs, delphiniums boast a more striking appearance, offering a vibrant array of colors to harmonize with any garden or color scheme. Here are some standout options for cultivating these stunning blooms in your own backyard:
King Arthur
Delphiniums are truly stunning flowers, as exemplified by this particular variety with its majestic blend of deep purple and blue hues on the petals and a crisp white center. The delicate brushstrokes of nature have seemingly come together to create a masterpiece that is nothing short of breathtaking. For gardeners in Zones 3-8, this beauty can thrive in full sun without becoming scorched, reaching heights of up to six feet tall.
Galahad
For those who adore the striking combination of pure white blooms against a solid green backdrop, Galahad is an absolute must-have. This stunning variety can reach impressive heights of 4-6 feet under ideal conditions, showcasing its vibrant white flowers on a multi-tiered stem that’s sure to grab attention. As part of the Pacific Giant series, it thrives in Zones 3-8, consistently providing a cascade of beauty throughout the growing season.
Million Dollar Blush
The ‘Million Dollar Blush’ variety stands at a relatively compact height of around 2-3 feet, making it an ideal choice for gardeners concerned with wind damage. Its blush pink blooms feature large, double petals that appear in mass formations. This type of delphinium is remarkably adaptable, thriving in both partial shade and full sun conditions within USDA Zones 3-7.
Notably, ‘Million Dollar Blush’ demonstrates greater heat tolerance compared to other varieties, rendering it a suitable option for gardeners seeking to grow delphiniums despite warmer climates.
Highlander Blueberry Pie
This particular delphinium stands out with its whipped cream-inspired charm. Its stunning double-flowered blooms boast a unique two-tone effect, transitioning from a soft pink hue to a vibrant blue as they reach maturity. A creamy white center adds an extra touch of elegance. Notably, this cultivar is shorter in stature than others in the same family, making it an ideal choice for cut flower arrangements or gardens where height is not desired.
Additionally, its compact growth habit makes it suitable for inclusion in garden borders without overwhelming the surrounding plants. It thrives in USDA Zones 3-7.
Magic Fountain White
The Magic Fountain series’ latest addition is an ode to vintage charm. What sets it apart is the striking contrast between its pure white petals and dark centers, which creates an undeniable sense of elegance. This compact delphinium stands at a height of 2-3 feet, making it an ideal choice for smaller spaces or containers. While it can thrive in shadier areas, it’s equally happy basking in the sun.
As such, it’s an excellent option for gardeners in Zones 3-7 looking to add some delphinium flair to their containers.
Black Knight
The showstopping combination of deep blue to purple petals and a bright bumble bee-colored center on this statuesque giant delphinium makes it an instant winner. As a hardy perennial, it thrives in zones 3-8 and can reach heights of around 5-6 feet, making it an excellent choice for those new to growing these stately flowers. This particular variety is part of the Pacific Giant series, offering a reliable and low-maintenance option for gardeners.
Astolat
The ‘Astolat’ larkspur, also known as candle larkspur due to its unique flowering habit, is part of the elatum species. Its stems grow up to 4-6 feet tall, making wind protection essential to prevent damage. The blooms themselves feature subtle creamy white centers and a range of purple to vintage pink hues. As a perennial hardy in Zones 3-8, ‘Astolat’ thrives in full sun, tolerating moderate heat levels when properly fed and watered.
Highlander Bolero
Standing out from the crowd, ‘Highlander Bolero’ delphiniums boast a unique charm. Its blooms feature small, tightly packed petals on large flower heads that showcase a stunning two-toned color scheme – think electric blue and pinky purple hues with creamy centers. The result is a mesmerizing tie-dye effect that’s hard to ignore. This compact perennial, which grows between 2-4 feet tall, makes it an ideal choice for gardens that are susceptible to wind.
In addition, its smaller stature allows it to thrive in zones 3-7, as long as it receives at least 6-8 hours of direct sunlight each day.
Cliveden Beauty
The ‘Cliveden Beauty’ variety of delphinium boasts delicate pastel baby blue blooms in a single form, evoking the charm of a quintessential Victorian manor flower garden. Its long stems of fountain flowers make it a striking addition to any bouquet or arrangement. As part of the Belladonna range, this delphinium tends to grow between 2-4 feet tall and 24 inches to 36 inches wide.
While some Belladonna delphiniums can be finicky to cultivate, ‘Cliveden Beauty’ is a longer-lived option that rewards seasoned growers in zones 3-7 with its beauty and resilience.
Princess Caroline
If you’re not fond of the classic blue-to-purple or vintage pink and white hues, Princess Caroline offers a unique and stunning alternative. As it ages, this variety develops a range of coral tones, making it a show-stopper for gardens and floral arrangements alike. A member of the elatum species, ‘Princess Caroline’ produces an abundance of double-headed, fountain-flowing blossoms on sturdy stems that reach 2-3 feet in height. This variety thrives in partial shade in zones 3-7.
Growing Delphiniums From Seed
Growing delphiniums from seed offers a cost-effective way to enjoy these stunning flowers while also expanding your color palette and variety options. These plants thrive when direct sown or transplanted, provided they receive suitable weather and soil conditions. In their second to third year of growth, delphiniums typically bloom most profusely, although some newer varieties are annuals that flower in the first year.
For added convenience, allow some flowers to mature and develop seeds, which will then self-sow for the following year. Newer delphinium varieties have also shown improved resilience to extreme temperatures, making it worthwhile to collect your own seed to save for future seasons. Delphinium seeds typically germinate within 10-20 days in temperatures ranging from 65-70°F. Start sowing eight weeks before the last frost of spring or direct sow in early summer.
Delphinium seeds can be notoriously finicky when it comes to starting, regardless of whether you’re using transplanting or direct sow methods. A helpful step in triggering germination is cold stratification. This involves storing the seeds in the fridge for a few months before sowing or placing them between a moist paper towel and plastic bag in the fridge for 36 hours prior to planting. To get started, sow the seeds about 1/8 inch deep in starting mix.
When it comes time to transplant, prepare the soil with compost and harden off the seedlings before spacing them 12-18 inches apart. In some cases, it’s unnecessary to pinch out seedlings, as certain varieties require prompt flowering. For these plants, maintain a temperature of around 50-55°F.
How to Care for Delphiniums
When transplanting new delphiniums, ensure the holes are no deeper than the original pot and filled with a rich compost mix. Water thoroughly, but avoid over-saturation. These plants thrive in full sun (6-8 hours) and may require staking for larger varieties to protect against wind damage. To promote healthy growth, apply a high-quality liquid fertilizer every two weeks during the blooming period.
In the fall, mulch around the base of the plants, keeping it approximately two inches thick and away from the stem. Delphiniums are heavy feeders, so consider side-dressing with compost or manure as they begin to flower. To multiply your delphiniums, allow pollinators to do their job and let seed pods mature. For continued blooming and growth, deadhead spent flowers or cut back stems to the base.
How to Multiply Delphiniums by Taking Cuttings
To multiply delphiniums, take cuttings from new shoots that emerge in spring. As herbaceous perennials, these plants die back to the ground each year, leaving their roots intact for the next growing season. When propagating using basal cuts, be sure to sever the stem below where it meets the soil, ensuring a solid base for rooting. Optional rooting hormone can aid in the process, though its application is not always necessary.
For optimal results, divide large clusters of perennialized delphiniums at their roots and relocate them throughout your garden. Timing-wise, morning hours are ideal for any propagation technique. Once transplanted, provide developing plants with protection from extreme temperatures, wind, and moisture fluctuations. Aim to maintain a consistent soil level humidity, avoiding overwatering that can significantly reduce the success rate.
Delphinium Pests and Problems
Delphiniums can be finicky when they’re young, but once established, they thrive with minimal care. These flowers are a pollinator’s delight, attracting butterflies, bees, and hummingbirds alike. However, their nectar-rich blooms also attract less desirable visitors, such as slugs and snails, caterpillars, aphids, mites, and leaf miners.
One of the key benefits of growing delphiniums is that they’re toxic to herbivores like rabbits and deer, making them a great option for gardeners who’ve struggled with these pests. Just be sure to exercise caution when handling the plants, as they can cause skin irritation and should not be ingested.
Delphiniums are also susceptible to several common diseases, including powdery mildew, bacterial leaf spot, crown and root gall, botrytis blight, and stem canker.
The latter is a particularly insidious fungus that can spread through damaged roots and cause significant damage. Symptoms include water-soaked lesions on stems and petioles, followed by yellowing leaves and eventual plant death.
To avoid these issues, make sure to provide good airflow between plants, avoid overwatering, and keep your delphiniums healthy with a balanced fertilizer. Remove any diseased plants and replace them with disease-free seedlings.
By following these simple tips, you can enjoy the beauty of delphiniums in your garden without too much fuss.
