If you've been gardening for a while, you may have come across two beautiful, spiky flowers often referred to interchangeably: Delphinium and Larkspur. While they both share similar characteristics, such as their tall flower spikes and vibrant colors, there are notable visible differences between the two. However, the confusion doesn’t end with their appearance; the names themselves are part of the reason why people often mix them up. So, let’s take a look at the differences between these two flowers, why they share similar names, and what leads to the ongoing confusion.
Why the Names?
Both Delphinium and Larkspur have earned their names from similar features. The term "Larkspur" traditionally refers to species from the Consolida genus, such as Consolida ajacis, which is an annual. The name "Larkspur" comes from the flower’s resemblance to a bird's spur, or the hind claw of a lark. "Delphinium" (the botanical name) is derived from the Greek word "delphinion," meaning "dolphin", which references the shape of the flower’s spurred petals resembling the curved shape of a dolphin’s nose. Despite this, the common name "Larkspur" is often used for both flowers, leading to the confusion.
This overlap in terminology likely arose because both plants produce spiky, upright flower stalks, often in shades of blue, purple, and white. Their visual similarities have caused gardeners and flower enthusiasts to mistakenly use the same name for both, even though they belong to different genera. Delphiniums are typically more robust perennials, while Larkspurs are often annuals.
Botanical Differences
The main botanical difference between Delphinium and Larkspur lies in their genus. Delphiniums belong to the Delphinium genus, while Larkspurs are part of the Consolida genus. Delphiniums are typically perennials, meaning they return year after year, growing larger and more established over time. Larkspurs, on the other hand, are annuals in most cases, meaning they complete their life cycle in one growing season. The confusion is understandable because many gardeners may only know the flowers by their common name, Larkspur, and not realize that some Larkspur varieties are short-lived annuals while Delphiniums are long-lasting perennials.
Growth Habits and Appearance
Delphiniums are typically taller and more robust than Larkspurs. They can reach 120 to 180 cm in height, making them excellent for the back of flower beds or as a backdrop plant. Delphinium flowers tend to be larger and more dense, with double flowers that have multiple layers of petals. They come in a wide range of colors, including rich blues, purples, pinks, and whites.
Larkspurs, in contrast, are generally shorter, growing to about 30 to 120 cm in height. Their flower spikes are typically looser and more delicate, often with single flowers rather than the fuller blooms of Delphiniums. Larkspur flowers are commonly blue but can also be found in shades of pink, purple, and white. Larkspurs are also annuals, meaning they need to be replanted every year, while Delphiniums are perennial and will return to your garden year after year with proper care.
Why the Confusion?
The main reason for the confusion between Delphiniums and Larkspurs is that they belong to two different genera but have similar characteristics, including their flower shape, color, and flowering habit. Both plants produce spiky, column-like flower stalks, often in hues of blue, purple, and white, and both are favored by gardeners for their ornamental value. Moreover, since Larkspurs are often referred to by this common name in the garden, Delphiniums, which also fit this description, are mistakenly called Larkspur as well.
Additionally, some species within the Delphinium genus are also commonly referred to as Larkspur, especially in casual gardening settings, further blurring the lines. For example, Delphinium ajacis, a variety that blooms in shades of blue and purple, is sometimes called "annual Larkspur," which only adds to the problem.
Growing Conditions
Both Delphiniums and Larkspurs prefer full sun and well-drained, moderately fertile soil, but they differ in their lifespan and care needs. Delphiniums require more maintenance, especially in areas with hot summers, as they may need support to prevent their tall stems from bending or breaking. They also need to be divided every few years to maintain healthy growth.
Larkspurs, on the other hand, are more low-maintenance and can tolerate slightly drier conditions, making them an easier option for gardeners who want annual flowers without the long-term commitment of perennials. Larkspur is often sown in the spring and completes its lifecycle in one growing season, while Delphiniums can live for several years with proper care.
In the summary, while Delphiniums and Larkspurs share many visual similarities, their differences in genus, growth habits, and lifespan set them apart. The confusion between the two comes from their similar flower shape, common name overlap, and shared ornamental appeal in gardens. Understanding the botanical differences between Delphinium (perennial) and Larkspur (annual) can help gardeners choose the right plant for their garden needs, whether they are looking for long-lasting beauty or seasonal splendor. Regardless of the confusion, both flowers are stunning choices that will add height, color, and elegance to the garden space. And after all that, please make sure to take a look at our favorite blue shade of Delphinium: Delphinium Blue Cloud
