Certain flowers open and close their pedals at night in response to light and temperature changes. The interior surface of some flowers expands when it's warm, yet shrinks when it's cool. When the interior surface tightens, the flower's exterior surface becomes larger than its interior, making it appear closed. The opposite effect occurs with flowers that open at night.
A crocus is a plant that has a flower, which closes at night. Most varieties of crocus plants flower in the early springtime occasionally when snow is still present. The saffron crocus is the only species to flower in the fall. These plants produce blue, violet, yellow, white and striped blooms. They are low maintenance plants and known to multiply readily, according to the National Gardening Association, a gardening organisation. The pedals of crocus open in full to moderate sunlight.
The morning glory has vines which open as flowers in the morning, hence its name. The plant has over 500 different species, according to Fine Gardening, a plant resource website. These plants require full sunlight during daytime hours when they yield funnel-shaped blooms of red, purple, yellow, white and blue. Their vines grow and wrap around structures. They have dense, heart-shaped foliage, which is green in colour.
A moonflower blooms in at night. Each plant usually produces four to six white or pink, aromatic flowers. The moonflower opens as the sun sets and remains open until sun rise in the morning. It grows to approximately 15 feet tall and has big leaves. A moonflower is an annual.
The primrose is a nighttime flowering plant. When the sun goes down, the plant produces yellow blooms. It only flowers from May to July. Primose is generally known as a wild flower and prefers a dry environment. It's a biannual plant, which means it reseeds itself in the same basic area where it's planted. According to Gardening Know How, an online gardening resource, primrose supposedly has a number of medical uses, including headache relief, hair regrowth and the ability to induce labour.