Pink Rain Lily, Zephyranthes grandiflora

Pink rain lily in bloom.

Pink rain lily in bloom.

Zephryanthes is a genus of about 70 species in the Amaryllidaceae (amaryllis family) native to southern North America, Central America, and South America, with common names including rain flower, rain lily, and zephyr lily (the closely related Habranthus also has the common name rain lily). One of the most common of these tender bulbs is the pink rain lily, Z. grandiflora (=Z. carinata, and often incorrectly listed as Z. rosea – which is really a Cuban species with much smaller flowers – or Z. robusta – which is a synonym of H. robustus, a Brazilian species with smaller, paler flowers on taller scapes) from Northern Mexico to Guatemala. In mild climates pink rain lily is used as a landscape plant for its attractive foliage and big flowers, but in the Midwest it is frequently relegated to container culture since it is only hardy in zones 7-10 and is easy to grow in pots.

Each reddish bulb has a tuft of grass-like leaves.

Each reddish bulb has a tuft of grass-like leaves.

Pink rain lily is a perennial, with a tuft of outward-spreading grassy foliage growing from a tunicate bulb with reddish skin. The 4-6 long, narrow, strap-like green leaves are slightly glossy or shiny and may be reddish at the base. The foliage may be persistent or die back, depending on the conditions.

The erect, funnel shaped flowers are borne singly on the end of erect hollow scapes. The tightly furled, dark red buds emerge from the bulbs and the stalks elongate 10-12 inches before the flowers open. Each pink flower with a white throat can be up to 4 inches across. Each has 6 tepals (3 sepals and 3 petals that look the same), a long white style with a three-parted stigma that thrusts out to one side, and floppy, golden anthers. The flowers open out flat at midday and close in the afternoon. Although each flower only lasts one to a few days (depending on temperature and sunlight), there can be multiple flushes of blooms throughout the season. Other members of the genus bloom only once in spring or autumn.

The solitary flowers (C) emerge from tight buds (L). Each has a three-parted stigma and golden anthers (R).

The solitary flowers (C) emerge from tight buds (L). Each has a three-parted stigma and golden anthers (R).

Pink rain lilies typically bloom after a soaking rain.

Pink rain lilies typically bloom after a soaking rain.

In their native habitat the flowers typically emerge a few days after a soaking rainstorm after being dry for a period of time. In cultivation they will bloom without being subjected to cyclical droughts, but even in containers outside during the summer flowering seems to occur more readily after thunderstorms. Cycles of drying and watering encourages the bulbs to bloom, but they will still bloom in bursts if kept evenly moist year-round. Indoors they can bloom at any time of year.

Pink rain lilies grow well in containers.

Pink rain lilies grow well in containers.

Plant the bulbs outdoors in the spring after all danger of frost is past in full sun and soil rich in organic matter. The top of the bulb should be about an inch under the soil surface and 2-4” apart (or closer in containers as they do best when crowded and slightly pot-bound). They are most effective planted in groups or clumps. These bulbs do well in the ground during the growing season, but it may be easier to plant them in containers to place outdoors in the summer, then bring the whole container indoors for the winter.

Very rootbound pink rain lilies.

Very rootbound pink rain lilies.

Although they tolerate dry conditions, foliar growth and flowering will be improved with regular watering and fertilizer. Plants need to be protected from frost, bringing those in containers indoors before the first frost in order to keep the foliage growing. Plants kept in containers over the winter should be kept on the dry side and watered infrequently until spring. Plants in the ground should be dug after the first frost kills the leaves and then should be stored for the winter in slightly moist peat or vermiculite in a cool location.

Rain lilies produce offsets from the original bulbs, multiplying readily.

Pink rain lilies are most commonly availble as bulbs.

Pink rain lilies are most commonly available as bulbs.

You can purchase bulbs and sometimes potted plants. The dried bulbs may take a season or two to become established and bloom regularly. Container-grown plants should be divided every four years or so. Like many species of Zephyranthes, pink rain lily bulbs and all parts of the plants contain toxic alkaloids that can cause vomiting, convulsions, and death if ingested. Most nursery stock is self-sterile and unlikely to set seeds.

– Susan Mahr, University of Wisconsin – Madison


Download Article as PDF


Additional Information

One thought on “Pink Rain Lily, Zephyranthes grandiflora

  1. Rain lily is only hardy in zones 7-10 so it is often used in containers. Rain lily is easy to grow. People love it for the attractive foliage and big flowers. Each pink flower with a white throat can be up to 4 inches across. Although each flower only lasts one to a few days ( depending on temperature and sunlight ) there can be multiple flushes of blooms throughout the season. Although they tolerate dry conditions, foliar growth and flowering will be improved with regular watering and fertilizer. I have a friend that has something very similar to this and she calls them Rocket lily’s.

Leave a Reply

Your email address will not be published. Required fields are marked *

While the University of Wisconsin Colleges and the University of Wisconsin - Extension do not regularly review content posted to social media sites, the administration shall have the right to remove any content from any official site for any reason, including but not limited to content deemed threatening, obscene, a violation of intellectual property rights or privacy laws, or otherwise injurious or illegal.

Public opinions/comments posted on this site do not necessarily reflect those of UW-Extension/UW Colleges.