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.
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.

→ 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.

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

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!