Ipomoea alba - Evening Glory

On warm summer nights, as soon as night falls, the large round flowers, white or pale pink, of this Ipomoea alba, also known as Moonflower, emerge, betraying their presence with their fragrance. The flowers close before noon in sunny weather and stay open longer in cloudy weather. This plant, native to tropical America, is a giant perennial in its country of origin, but it shows rapid growth that allows us to cultivate it as an annual in our climates with hot summers. It will decorate the veranda or greenhouse with its dark green heart-shaped foliage in large containers, protecting it from our harsh winters. It is a generous but voracious plant, appreciating fertile soil, regular watering, and full sun.

Ipomoea alba is a perennial evergreen that flowers at night and in cloudy weather, originating from tropical and subtropical regions of the Americas, from northern Argentina to northern Mexico, and up to Florida. Formerly classified in the Calonyction genus, it is now assigned to the Ipomoea genus, belonging to the Convolvulaceae family. It is an herbaceous plant with voluble stems that can reach 30m (98ft) in its native habitats, when its vegetation is not destroyed by frost. When grown as an annual, it will reach about 3m (10ft) in all directions. Its leaves are entire or trilobed, measuring 5 to 15cm (2 to 6in) long, heart-shaped, and dark green. Flowering occurs from July to September, with large, very round flowers, pink or white, measuring 8 to 14cm (3 to 6in) in diameter, in wide funnel-shaped or almost flat corollas, highly fragrant, carried by long peduncles. They open quickly in the evening, remain open at night until the rays of the sun hit them in the morning. Flowering is followed by the formation of hard, pointed, ovoid capsules, measuring 2 to 25mm (0 to 1in) in diameter, containing seeds with sparse hairs that are easy to sow.

The Moonflower is a fabulous, generous plant that will climb a warm wall where it will find conditions reminiscent of its origins. A southwest exposure seems favourable to enjoy its flowers for longer in the morning. The heat radiated by the wall will be beneficial to it. It can easily be grown in large pots that can be placed on the terrace during the summer to fill the air with fragrance on summer evenings. It is only in the mildest areas of our country that it will truly show its perennial nature, taking up all the space required by its natural luxuriance. Ipomoea alba can also be grown in pots and pinched like chrysanthemums, which makes it very floriferous. Its flowers can also be used to decorate a table on a festive evening.

This plant gets its name from the fact that it blooms its flowers under the moon, but also from the lunar shape of its flattened corollas.