How to Grow Larkspur Flowers

About Growing Larkspur Plants in Your Home Flower Garden

Most likely, you first saw the tall and stately spikes of Larkspur flowers growing in your grandparent’s flower garden. When in bloom, these big flower spikes are lovely in the garden and indoors in vases. They are members of the Delphinium family and are related to Buttercups. There are many varieties, and it should not surprise you that they range in height from one to seven feet. When growing larkspur plants, place taller varieties at the back of the flowerbed. If you’ve never grown this plant before, what are you waiting for!? Buy some Larkspur seeds and plant them this spring.

Best of all, tall-growing Larkspur plants produce flowers that burst into bloom when many other flowers are still weeks away.

Did you Know? Larkspurs can be poisonous to some animals, most notably cattle. However, home gardens usually do not have cattle grazing in the flower beds.

Larkspur Plant Specifications

Flower Colors: Colors include light and dark pink, blue, rose, lavender, and white.

Flowers Bloom: Spring, Summer, or Fall, depending upon variety.

Plant Height: 3′ – 5′

Hardiness Zones: 2 – 9

Light Requirement: Full sunlight

Deer Resistant? Yes. Deer seldom bother this plant.

Toxic: Yes, very much so.

Ideal Soil pH: 5.5 – 7.0.

Native To: North America

Plant Type: Perennial. It is often grown as an annual in colder regions of the country.

Botanical Name: Consolida Orientalis

Light Requirements

It is important to grow Larkspur plants in full sunlight. Give them 7 – 8 hours of bright, direct light.

If the plants get too little sunlight, they grow lanky or leggy. Then, the plant and flower stems become too thin to support the weight and fall over.

Even with full sunlight, you may want to stake these plants to help protect them from damaging high winds.

Are Larkspur Plants Edible?

NO!!

All parts of the plant are inedible. Rather, they are toxic to humans, pets, and farm animals.

Keep this plant away from small children and pets.

Medicinal Uses for Larkspur

Larkspur seeds are used for some medicinal applications. Among them are:

Dropsy
Spasmodic Asthma

Caution: Because this plant is toxic, we recommend you do not prepare these remedies yourself, unless you are properly trained to do so.

Larkspur Flowers Plant Propagation

The plants are started from seed. Directly sow Larkspur seeds into your flower garden after all danger of frost.

Sow Larkspur seeds early in the season and cover lightly with 1/8″ of garden soil.

Space the plants 4 inches apart. The final spacing should be 10-12 inches apart.

Larkspurs are Rhizomes. You can separate the rhizomes of established plants and replant them in new areas.

Days to Germination: 10 – 15 days.

How to Grow Larkspur Flower Plants

Larkspur plants grow their best in full sun. They tolerate partial shade. However, the plants grow lanky and leggy under lower light conditions. They are very easy to grow and grow rapidly.

The plants do well in average soils and cool weather. Yet, we still recommend mixing in an ample amount of compost at the planting site.

The soil needs to be kept moist to feed their rapid growth. Water them during dry periods, once or twice per week.

Stake the plants in areas that receive high winds.

Add a general-purpose fertilizer once a month until after they have bloomed.

Cut blooms just before they peak. Place them in a vase and arrange them with other flowers, or alone by themselves.

Once your Larkspur plants are established, they will grow well until the first frost. The plants are annuals and highly susceptible to frost.

Pruning Larkspur Flowers

Remove any dead, sickly, or diseased leaves and stems as soon as you spot them. Diseased material should go into the trash. DO NOT put it into your compost pile. The disease may not be destroyed by the heat of the composting process. And it can spread to all of the material in your compost.

Can You Grow Larkspur Flowers in Containers?

Larkspur plants are a very tall-growing plant. So, they are not commonly grown in flowerpots or containers. However, with a large enough container, you may want to use them on your patio or deck in some situations.

Like any container-grown plant, they need extra care and attention. Here’s how:

It is important to have a drain hole to allow excess water to drain from the pot.
Keep an eye on the moisture level. Outdoors, check the plants every day or two, especially in extended periods of hot, dry weather. Keep the soil moist, but not wet. It is okay to let the top of the soil begin to dry between watering. When watering the plants, thoroughly wet the soil. Excess water will drain through the hole in the bottom of the flowerpot.
Nutrients in a flowerpot are limited. So, use fertilizer spikes to feed the plants. Or, apply a light solution of liquid fertilizer once a month.
Select a sunny location on your deck.

Remember, they are a toxic plant. If you have small children or pets, you may not want them on a patio or deck.

Insects and Plant Disease

Larkspur are very susceptible to plant disease. Fungal disease is common, most notably Sclerotium rot which yellows leaves and wilts plants. Larkspur is also affected by mildew. Remove all diseased parts of the plant. Then, treat affected plants immediately with a general-purpose fungicide. Remove seriously diseased plants to keep the disease from spreading. Do not put diseased plants in your composter.

Insect problems are less frequent. Organic or chemical insect repellents are effective against most pests.

Plant Problems – Find the causes and cures.

Winterizing Larkspur Plants

In warmer parts of the country, you are likely growing Larkspur as a perennial. After frost has killed the plant for the season, cut it back to the ground. Then, place the vegetation into your composter, or in the trash. Finally, apply a light layer of mulch. This protects the roots from freezing over the winter months.