Delphinium, how to care for tall larkspur flowers

Larkspur, delphinium

Delphinium, also called larkspur, is an amazing plant that blooms from June to October.

Key Delphinium facts

Name – Delphinium
Family – Ranunculaceae
Type – perennial or annual

Height – 20 to 60 inches (50 to 150 cm)
Exposure – full sun

Soil: ordinary, well drained  –  Flowering: summer → mid-fall

Sowing or planting are the only things to actually do for this plant, because delphinium require absolutely no care at all.

Sowing and planting delphinium

For perennial and hardy delphinium species

Perennial and biennial larkspur species can be sown in spring and summer, preferably under a cold frame if early in spring.

Delphinium blooming with blue and white paniclesIt is best to plant delphinium seedlings from their nursery pot to the ground in September. This gives the plantlings time to properly develop their roots before winter. They’ll grow back stronger in the following spring.

  • Delphinium loves rich soil, feel free to amend it when planting with fertilizer or compost.
  • It loves emplacements that receive a lot of sun.
  • Avoid spots where the wind howls through, or else, simply stake the plant.
  • Keep a distance of 16 inches (40 cm) between plants.

→ Propagate perennial delphinium through crown division in spring.

Sowing annual delphinium cultivars

When sowing from seed, prefer sowing in fall or until spring while avoiding frost spells.

You can sow directly in the plot if you wait for the last frost date to pass (end if spring, usually), otherwise try sowing under cover or indoors, in a tray.

Enrich the soil with special flower plant soil mix and granulated organic fertilizer to enhance the blooming and make it more dense.

  • Expect to wait at least 4 weeks before being able to transplant to the ground.

Care for Delphinium and pruning

Caring for delphiniumCut stems off after the blooming, this will trigger appearance of more new flowers.

For perennial delphinium, cut back to the shortest in fall and, if needed, protect the base in colder areas.

  • Delphinium don’t stand to the wind well if not staked.

Learn more about delphinium, larkspur

Varieties of delphiniumThis cute plant bears distinctive long floral scapes that uphold beautiful white, blue or pink flowers.

Its great height, often taller than 3 feet (1 meter), makes it a good plant to settle at the back of a flower bed where it will produce an nice bushy backdrop.

Some varieties are particularly tall and colorful, such as the beautiful Pacific Giant Delphinium.

It also makes for great bouquet flowers that will keep for a long time – even a bouquet of dried flowers!

Smart tip about delphinium, larkspur

  • Cut a few delphinium flowers off the bush in summer, and set them in a vase: you’ll be surprised at how long they last in such a bouquet!

Images: iStock: kynny; Pixabay: Jaqueline Henning, Светлана Гурьева; Public Domain: Lisa Ann Yount