Evening primrose

There are about 125 species of evening primroses, or matsuyoi-kusa ("waiting-for-evening plants"), and all are native to the Americas. Most have yellow flowers, but some have white or pink blooms, such as the species pictured above. This is Oenothera speciosa , commonly known as "pink ladies" or "showy evening primrose." In Japanese, it is called hiruzakitsukimi-sou (literally, "day-opening moon-viewing plant"). Its buds open toward dawn and the delicate pink-and-white flowers can last for two days. The first evening primrose to reach Europe was the tall, yellow-flowered species O. biennis . It arrived in the early 1600s but soon escaped from botanical gardens, and now it flourishes as a wildflower, often in poor, sandy soils and wasteland. Like poppies, its seeds are long-lived and can wait in the ground for up to 80 years. If the soil is disturbed, any seeds that are brought closer to the light will then spring into life. The seeds of O. biennis also produce a rare oil, or essential fatty acid, known as GLA (gamma-linolenic acid), which is used in treating skin complaints, rheumatoid arthritis, cancer and diabetes. As with many night-flowering plants, evening primroses have a sweet fragrance to attract moths. Their pollen is held together with fine, sticky threads so it can only be gathered by a particular type of bee. Although rather fussy about suitors, the plants spread rapidly, and the pink version, as I am discovering in my garden, also sends out underground runners. Last year, I planted one young plant, but now I have little "pink ladies" popping up all over the place!