The bright yellow-orange flowers and finely divided gray-green foliage of the california poppy look best when planted in large drifts, although it grows well even in crevices of rockeries. Flowers appear in spring and last throughout the summer. They are suitable for cutting but will close at night. Place flowers in water immediately after cutting. Plants grow 12-20 inches high and spread up to 20 inches. The plant is not suitable for the tropics, but will grow well in most other climates. It must have full sun and well-drained soil, but will tolerate poor soil. The flowers are solitary on long stems, silky-textured, with four petals, each petal 2–6 cm long and broad; their color ranges from yellow to orange, and flowering is from february to september. The petals close at night or in cold, windy weather and open again the following morning, although they may remain closed in cloudy weather. The flower is a slender, dehiscent capsule 3–9 cm long, which splits in two to release the numerous small black or dark brown seeds. It is perennial in mild parts of its native range, and annual in colder climates; growth is best in full sun and sandy, well-drained, poor soil.