THE extended growing season this autumn has seen evening primrose almost in full flower in recent days. Although this lovely flower can continue into October in good years, it generally looks much more tired and bedraggled at this late stage.
Evening primrose is as tall as a good foxglove and carries lots of large bell-shaped yellow flowers. These are produced in a long succession from elongated buds near the top of the stems. The large flowers, 5cm across, are very showy and can be seen from quite a distance.
This once-popular cottage-garden flower is now probably better known for the tonic effects of the oil crushed from its seeds. It is used in herbal medicine for eczema and period pain, although clinical trials have proved inconclusive.
The common evening primrose is native to North America. It is grown in many parts of the world as a garden flower and has become naturalised in a few places here. Though called evening primrose because of its yellow flowers, these are of a brighter, light lemon colour than the soft pale yellow of native primroses.
It is not related to primroses at all, being part of the fuchsia and willowherb family. The evening part of the name comes from its night-flowering habit as it is pollinated by moths. It has a light fragrant scent on a warm evening.
The seeds are very small and copiously produced, easily carried by rainwater, or in mud, and spread around to produce young plants. This species is annual or biennial, the tall stems withering after flowering. New seedlings generally replace the old plants and it usually appears in eye-catching drifts of dozens of plants.
It is very easy to grow as a garden flower, so easy that it sometimes appears mysteriously in gardens, though not planted, the seeds having been transported there inadvertently. Evening primrose likes well-drained soil in full sunshine. It does all right in poor, sandy soil but does not grow as tall.
The seeds can be sown in spring in a seed tray and pricked out into small pots for planting in the garden. Fast-grown plants will flower the same year, others will flower the following year from mid-summer to autumn.
If you have a bed or border, with mixed plants, or a semi-wild area with dry soil, open to the sunshine, and you like to let plants wander to some extent, this flower might suit. There are other evening primrose, or oenothera, species, but none as elegant.