EVENING PRIMSOSE

Family ONAGRACEAE
Oenothera species
Perennial/Biennial/Annual

An attractive group of hardy annuals, biennials and perennials from the Americas.

Among the biennials Oenothera biennis, North America, grows to five feet, bearing yellow flowers, which open late in the day.
It has various forms, notably grandiflora and lamarckiana and one of garden origin named “Atterglow” which has effective red calyces.

Among the annuals are the Californian Oenothera bistorta with yellow and red, four-petalled flowers, an inch across, spotted red at the base, opening in the daytime;
Oenothera amoena, one to two feet, with rose and crimson flowers, also from California;
Oenothera odorata, one to two feet, from Chile, with yellow flowers fading to red before falling. Only six inches high,
Oenothera trichocalyx usually dies after flowering.
Oenothera fruticosa, known as Sun-drops is a perennial with golden yellow flowers about two inches across.

Sow the seeds in April in a sunny, well-drained position and thin the seedlings to six inches apart, or under glass in March for early flowering.

Propagation is from seed.

The flowering season is from midsummer onwards.

Œnothera – Evening Primrose

Of the Evening Primrose , “Evening” is accurate enough a character of one section of the family at least; but why “Primrose”?

There are two main sections, the hardy biennial, chiefly tall growers, and the dwarf or recumbent perennial tribes.

The best form of the former is Oenothera Lamarckii or Lamarckiana, sown in the open in May or early June, it produces a rosette of crinkled leaves, sitting flat on the ground, with forked fleshy roots.
In the following summer this throws up a woody branched stem, from three to as much as six feet high.
A fine specimen, with room to do itself justice in, is like a many-branches candelabrum, whose arms bear for many weeks a constant succession of large yellow flowers.

The biennial Œnothera is a night-blooming plant; after sundown the buds push off their envelope, and spread to the evening air with an almost momentary action.
The flowers of a good strain – and as there is much difference herein, it is worth while to get seed of a dependable kind – are funnel-shaped, three or four inches across, and their colour is a rich yellow, with a thought of green in it, remarkably luminous in the summer dusk.
When the last buds of the long spikes have expanded, the plant may be pulled up, and its room utilised.

The biennial Œnotheræ are raised from seed sown in June or early July; from a too-early sowing, the plants sometimes throw up small premature flower-spikes the first year.
The fine seed should be carefully sown in shallow drills in the open ground; the seedlings may be pricked out, or thinned and left in situ till the autumn planting season.
The plants require care in handling, as their roots are straggling, and their leaf-stalks brittle.
Plant out finally in groups or lines, in borders, in front of shrubberies or in waste corners; half-shady places may be utilised, but the root-run should in all cases be fairly deep and nourishing.

Oenothera bistora Veitchii is a half-hardy annual variety, about a foot high, with yellow flowers spotted with crimson.

Oenothera drummondii nana and Oenothera Rosea are hardy annuals, the first a foot high, with yellow flowers, the second six inches with rose-pink flowers.

Oenothera taraxacifolia, sometimes called a perennial, is best treated as a hardy biennial.
It is low-growing, and of a trailing habit, and resembles the perennial Oenothera macrocarpa, save that the flowers are white, with a pink flush as they fade, instead of clear yellow.

Of the perennial section the best is Oenothera macrocarpa, which has a somewhat woody trailing habit, the red stems and glossy leaves making a fine contrast with the large funnel-shaped blooms, of the same clear yellow as the flowers of Lamarckiana.
It should be planted, if practicable, among some stones, over which it may sprawl.
The flowers, which in cool weather remain open during the day, appear from July until the frosts.
Oenothera “M. Cuthbertson” is an upright grower two feet high; the stems and leaves have a red tinge; the flowers are clear yellow.

Oenothera fruticosa Youngii is dwarf, forming a compact tuft of leaves; the flowers are in clusters, about eighteen inches high.

Oenothera Frazeri is compact, about a foot high, yellow flowers.
All the perennial species should be planted in autumn or early spring, the latter for choice, as the newly-divided roots do not run all the risks of frost and wet.
Oenothera Frazeri and Oenothera macrocarpa may be raised from seed; as a rule it will be safest to sow in boxes or pans in June or July, and afford a little help in the way of water and shade