DELPHINIUM

Family RANUNCULACEAE
Delphiniuim species
Perennial

A race of hardy plants widely distributed over the northern hemisphere.
The foliage is elegantly lobed and divided and the flowers borne in spikes on branching stems.

Delphinium elatum, reaching to a height of three to six feet, has spurred flowers of blue, an inch or less across and, with Delphinium cheilanthum and Delphinium formosum, is believed to have been the main influence in the evolution of the present-day magnificent garden varieties.
Its form belladonna is a dwarf branching plant with florets of blue.
Delphinium cardinale, from California, has scarlet florets on three- to four-feet stems;
Delphinium nudicaule, from the same habitat, is of similar colour, but with partly closed florets on one-and-a-half feet stems.
There are many other species.

For gardens the varieties of elatum type are most used, and require a deep, rich, well-drained soil in sun or partial shade, good drainage, and ample moisture during growth.

Propagate by means of division, cuttings or seed.

The flowering season is in June and July and again in late summer.

Delphinium – Perennial Larkspur, Bee Larkspur.
Hardy Perennial
Eighteen inches to ten feet.
Flowers chiefly in shades of Blue, June and July.

(For annual Delphiniums see under Larkspur).
The perennial Delphiniums may be divided into tow main classes: the first consisting of what may be called the botanical varieties (“Delphinium species”, as the catalogues have it) such as Delphinium Cashmerianum, a fine blue about two feet high;
Delphinium Chinensis, blue, eighteen inches;
Delphinium nudicaule, orange-scarlet, eighteen inches. The last can be grown from seed without much trouble; sow in boxes about May, prick out when large enough, and in cold neighbourhoods or heavy soils winter in a frame.
“Zalil” or Delphinium sulphureum (the yellow Delphinium) formosum, bright blue, and formosum celestinum, pale blue, may be grown in the same manner.
The dwarf species known as the “Blue Butterfly” or “Queen of the Blues”, may also be considered as a bedding-plant. If sown in good light soil about the end of March, it will form bushes eighteen inches high, covered in July with flowers of a very beautiful cobalt blue; with ordinary care the plants will survive for several years.

The second class consists of the tall-growing Hybrid Delphiniums which have taken such a prominent place in perennial gardening during the last twenty years.
A well-known Delphinium begins to throw up its shoots in March, and by May advances to a dome-shaped bush of handsome deep-cut foliage, above which rise in June and July the long spikes of close-set flowers, single or double, in many shades and mixtures of light and dark blue, purple and white.

The two most distinctive colours are a very dark purple-blue and a clear bright blue which better deserves the character “sky” than many others which obtain it. Many of the flowers have a black or a white centre or eye, and many show a mixture of colours, a shading together of crimson and blue, or violet and rose in the same flower, with a metallic sheen peculiar to the tribe.

Delphiniums will grow tolerably in almost any soil, but to produce nine-foot spires of blue, they require a deep and wide root-run in ground that is rich and rather light. The root-fibres form a dense mat and spread to a surprising distance from the base; there must therefore be no strong competitors or hungry shrubs within several yards of the clumps.

Established plants should have a good top-dressing of old manure spread round them in November, and a sprinkling of wood ashes and soot when the shoots first appear in March will do something to discourage the slugs who are fatally fond of the young foliage. If a clump sends up more than a dozen stems, the weakest should be cut out and some seven or eight of the stoutest left.

When these are about two feet high, they must be secured to stakes. It is the main fault of the hybrid Delphiniums that they are not self-supporting, but entirely dependant on the aid of sticks and string.

Young plants may have one stout stake six feet out of the ground; older clumps may need two or three, arranged in a triangle round the plant, which must be encircled with girths of tar-string as its growth advances. There is room for plenty of skill in arranging the stakes and ties so as to be inconspicuous and yet to provide safe anchorage in summer storms.

When the flower-spikes are over, about the middle of July, they may be cut off, but the stems should be allowed to stand until the autumn clearance. The advice sometimes given that they should be removed at once, to make the plants give a second crop of bloom is worthless; the second growth is a poor thing at best, and the proceeding is most unfair to the plant and entirely false economy.

In droughty weather heavy soakings of water, a yard or more away from the stems, will be very beneficial. Digging or forking among the mat of roots, under pretence of “tidying up”, must never be allowed.

If named kinds of Delphiniums are desired, plants must be obtained from a good hardy-plant nursery, and put out in February. For all purposes except those of the exhibitor and fancier, excellent plants may be had from seed. This should be of a really good strain.
Sow early in April in drills in fine soil, thin out and transplant in good time into a piece of good ground with an open exposure.

The plants should throw up small spikes the first autumn (sufficient to show the colour and habit); in November or February they must be put out into their final positions.
The following summer they will make four or five fine spikes; the next two years they will be in their glory.
After four or five years they deteriorate, and the new stock of seedlings should be ready to succeed the veterans.

The tall Delphiniums may be planted in groups of three in mixed borders, or in masses in large beds, or in long single lines or avenues as borders to shrubberies, always provided in the latter case that the roots of the shrubs do not impoverish the ground.

See also Larkspur