Delphinium Guide: How to Grow & Care for “Larkspur”

Our Guide to Delphiniums - Everything you will ever need to know! Tips for growing and caring for “Larkspur”
Pinterest LinkedIn Tumblr

Also known as Larkspur, Delphiniums are a genus that includes about 300 species of perennial flowers. They belong to the Ranunculaceae family. These flowers are appreciated for their tall stems, loaded with rich clusters of flowers.

Delphiniums have a rather wild appearance, which is why these flowers will surely remind you of dreamy cottage gardens. However, with adequate arrangements, you can easily integrate them into almost any garden décor. They are a great way to add some height and color to your garden, and due to their height and rich flowers, they also make for great cutting flowers for vases.

About Delphiniums

  • The name Delphiniums derives from the Greek word “delphinion” which means dolphin. It is believed that this plant got its name because delphinium flowers have a slight resemblance to the shape of a dolphin.
  • These flowers can grow wild all over the northern hemisphere.
  • Symbolically, larkspurs are the birth flowers of people born in July. They symbolize an open heart, generosity, and joy.
  • Delphiniums are toxic to both humans and animals.
  • Despite their toxicity, Delphiniums a.k.a Larkspur is still used in alternative medicine to treat a wide variety of illnesses from fluid retention to lack of appetite, intestinal worms, and even insomnia. However, medical practitioners warn that delphiniums are unsafe as they can cause lung failure, slowing of the heart rate, and low blood pressure.
  • On a more superstitious note, throughout history, larkspur has also been carried as a protection against scorpions and venomous snakes. It is believed that the plant repels these venomous predators. Some people go even as far as saying that it repels bad energy, and they use it to ward off evil spirits.
  • The Blue-purple larkspur flowers have also been used for centuries to create the blue textile dye.
  • These plants are resilient to most diseases and pests. However, they are vulnerable to slugs, especially in April and May. We advise you to use Nematodes or organic slug pellets to protect your plants from these annoying pests. Mildew can also be a problem, as well as fungal spots, gray mold, and root rot.

Delphiniums Features: An Overview

  • Delphiniums stand out due to their height, which can reach almost 2 meters with an average spread of half a meter. As such, it is best if you plant them at the back of your garden, or on the last row in flower borders.
  • They bloom in summer. Their dolphin-shaped flowers with white, brown, black, or striped centers. The centers are often called bees.
  • There are several delphinium varieties to choose from, the most popular ones being Belladonna delphinium, Delphinium Chinensis, New Millenniums, and Pacific Giants.
  • People mostly associate larkspur with blue or purple flowers. However, larkspur flowers can also be pink, lavender, red, and even white.
  • Delphinium flowers have no fragrance, but they have a rather clean smell.
  • The leaves have a palmate shape with 3-7 deep lobes.
  • Larkspurs have a short lifespan. They rarely last more than 3 years, so make sure to propagate them regularly, to always have young plants in your garden.

Growing Delphiniums

Delphiniums are sun-loving flowers, so make sure to find them a spot in your garden that benefits from full sun exposure. They thrive in USDA zones 3 to 7. They do not need special soil, but they will thrive in moist, well-drained soil. Rotten manure or homemade compost is a great way to enrich your soil naturally and give your plants a boost to grow taller.

If you lack garden space, you can choose more compact varieties that you can grow in pots on a patio or a balcony. Moreover, if you live in an area with strong winds, make sure to provide some shelter for your plants. Due to their height and light stems, they can be severely damaged by strong winds.

Blue Delphinium Flowers
Blue Delphinium Flowers

When it comes to supporting the flowers, you should stake the delphiniums when they reach about 30 cm in height. This usually happens towards mid-spring. Use twigs for young plants and upgrade to sturdier stakes as the plants grow. To encourage flowering, apply a liquid fertilizer once a month during spring and the flowering period. If your plants exhibit yellow leaves or they stop growing, it may be a sign that they need more fertilizer.

Once the flowering period reaches its end, deadhead the plants, by cutting the spent spikes. Once the blooming is completely over, cut the stalks to ground level and watch as new stalks grow within the same season. If you deadhead and cut the plants in time, you might enjoy the intensely colored flowers until early fall. Moreover, keep in mind that thinning is essential for these flowers. One-year-old plants should have one spike whereas two-year-old can have as many as three spikes. Older flowers can have as many as 50 spikes.

Planting Delphiniums

These flowers look best when they are crowded. However, overcrowding them can create a heavy environment, ideal for the development of mildew. As such, it is best to give these plants some space and plant the seedlings about 60-70 cm apart. As the plants grow, you will need stalking to keep their stems straight. The stems are hollow, and as they grow in height and bloom, they can sometimes collapse under their weight. To hide the stakes, you can plant medium height perennials in front of the larkspurs. We suggest echinacea, Foxglove, or lilies.

100+ Delphinium Seeds, From Amazon

When planting delphiniums, dig a hole add some manure at the bottom of the hole to ensure a good amount of nutrients. If your soil feels heavy, add some grit to it to improve drainage and to protect the plants during winter. Plant the delphiniums at ground level and press the soil around them to offer them proper support.

Watering Delphiniums

Like it goes with most flowers, the watering needs depend on the weather and the soil. As a rule of thumb, delphiniums require regular watering, especially during the dry summer months. The soil should have good drainage so that it can maintain moist without being soggy. You should never let the soil dry out completely. Compost and mulch will retain the moisture in the soil, and it will also help control the weeds.

Propagating Delphiniums

These flowers can be propagated from cuttings with minimum effort. With proper care, they will deliver an abundance of blooms in their first year.

When propagating from cuttings, cut them from the base of the plant in spring. After cutting the plants, try to plant them as soon as possible. Make sure to remove some of the foliage. Only leave a couple of leaves at the top of the cutting, enough to produce photosynthesis. After planting the new delphiniums, you can place them on a heated bench.

If you do not have a heated bench, you can place them on a sunny windowsill, but place a bag over the young plants to simulate a heat chamber. Mist the young plants regularly for a few weeks until they develop some healthy roots. Plant them in peat-free compost mixed with sifted garden compost and a little grit and perlite. Make sure to plant them at the same depth that they were planted as cuttings.


If you want to propagate from seeds, you can do it anytime from September to March. Use fresh seeds, as delphinium seeds are no longer viable after one year. If you do not know whether your seeds are fresh or not, plant several seeds at once, or even the entire package. Presoak the seeds to increase the germination rate and cover the seeds with a very thin layer of soil.

Seeds stratification is also a good method to improve the germination rate. Keep the seedlings in a warm location with temperatures ranging from 17 to 23 degrees Celsius. Mist them regularly, but make sure to only penetrate the top layer of soil, as delphinium seeds are sensitive to rotting.

Just like with cuttings, keep the seeds warm, using either a heated bench, a heat mat, or a plastic heat chamber. If you do not have a sunny windowsill indoors, you can help the seeds grow by using a grow light. Allow the plants to develop a good root system and a couple of leaves before transplanting them. Use a low strength fertilizer when transplanting the seedlings.

In Conclusion

As we already mentioned, these flowers are ideal for wild-looking gardens. They are easy to grow, and they add a lot of color and joy to any space. Nonetheless, they do require regular attention. Aside from regular watering, you also need to provide them with vertical support, regular fertilization as well as regular pruning and deadheading. However, they will reward your efforts with a gorgeous and long-lasting display of colorful flowers.

You can pair delphiniums with sunflowers, Hollyhocks, Tall grasses, Filipendulas, or Goat’s beard. You can also plant them next to peonies, chrysanthemums, roses, irises, or asters. Just make sure to plant them on the end row of a border, so that they don’t overshadow smaller plants.

Are you growing Larkspur? Share your experience in the comments below!


Miruna is an experienced content writer with a passion for gardening. She is the proud owner of an outdoor rose garden and an indoor collection of tiny succulents. She bought her first succulent 10 years ago - an adorable Echeveria Setosa. Now she owns more than 100 succulents and cacti of different colors, shapes, and sizes. Miruna is a versatile writer and, as you might have guessed, her favorite topic is gardening. Contact

Write A Comment