Gloriosa lily is generally planted in the spring from purchased or divided tubers. Gloriosa is grown as a perennial plant in warmer zones, but in colder regions, you can either grow it as an annual or dig up the tubers and store them for the winter to replant in the spring. It is a fast-growing plant that will reach full height and blooming maturity within a couple of months. Like all plants in the Colcicaceae family, gloriosa lily contains the highly toxic alkaloid colchicine in all plant parts, but especially in the tubers. The plant can be fatal to humans and animals if ingested. In cold-winter regions, gloriosa lily is grown as an annual, Or, it can also be planted in containers that can be buried up to the ground for the growing season, then dug up and stored in a protected area for the winter. The tubers can also be carefully dug up at the end of the growing season, stored for winter, then replanted in the spring.
Light
Gloriosa lily grows in full sun to partial shade. Especially in hot, dry climates, it does better with some protection from the hot afternoon sun, such as dappled shade from nearby taller plants. Shadier conditions might reduce flowering.
Soil
The soil should be rich and provide excellent drainage. Sandy or loamy soil are best. To enrich the soil, amend it with organic matter. Gloriosa lily grows well in neutral to slightly acidic soil.
Water
Gloriosa lily needs even moisture during the growing season from spring to fall. In the absence of rain, water it regularly while making sure there is good drainage, so the plant never sits in soggy, wet soil.
Temperature and Humidity
In its native environment, gloriosa lily grows at elevations up to 2,000 feet, where the daytime temperature is moderate, around 70 degrees Fahrenheit, and nights are cool, around 60 degrees Fahrenheit. As a garden plant, it will do best in similar circumstances. Gloriosa lily does not do well in hot, arid climates. In high humidity, on the other hand, gloriosa lily is in its element—think of the monsoon seasons common to its native habitat.
Fertilizer
Fertilize gloriosa lily about once a month with a diluted complete fertilizer during the growing season, less frequently when the soil is very rich. Too much fertilizer will not necessarily lead to a better bloom and can instead encourage the growth of foliage at the expense of flowers.
Types of Gloriosa Lily
The species form of gloriosa lily has flowers with bright red petals edged with equally bright yellow. There are also several named cultivars of gloriosa lily that offer flower variations. Some popular ones include:
‘Citrina’: This variety has yellow tepals with maroon stripes.‘Grandiflora’: This cultivar is known for its large golden yellow flowers.‘Lutea’: This cultivar has flowers of solid yellow without a trace of red.‘Rothschildiana’: This very popular cultivar has wavy-edged flowers with bright red petals showing yellow at the base.‘Greenii’: This is an unusual cultivar with creamy green flowers.‘Simplex’ : This variety has deep orange and yellow blossoms.‘Himalayan Select’: This striking type has ruffled flowers of rosy red and yellow-green.
Pruning
No pruning is necessary for the health of this plant, but when the stems die back after the flowering period is over, you can cut them back to ground level. But leave the foliage and stems in place while they remain green because this is the period when the plant is storing energy for its tubers.
Propagating Gloriosa Lily
Gloriosa lily is grown from tuberous roots, which remain dormant during the winter. These tubers can be lifted and divided to propagate new plants. Such division should done no more than every three years or so. Here’s how to do it. Fat, healthy tubers can take some time before they sprout, but as weather warms, they will accelerate their growth and will likely produce flowers in their first season.
How to Grow Gloriosa Lily From Seed
Gloriosa lily is normally propagated by dividing the tubers, as this is a fast method that also ensures the propagated plant will be identical to the parent. The plant can also be grown from seed, though this is a slower process that can require as long as three years before the seedlings develop tubers large enough to support flowering. Further, the plants generated from seed propagation will be true to seed only if you used seeds gathered from a species plant. Seeds collected from named cultivars may not come true, but will instead produce plants that look different than the parent plant. If you want to try your hand at growing gloriosa lily from seed, start the seeds indoors in mid-winter. First, soak the seeds overnight in lukewarm water, then plant them in small pots filled with potting mix, no more than one inch deep. Water to moisten the potting mix, and place the pot in a clear plastic bag to hold in moisture. Keep the pot near a warm south-facing window. When the seeds germinate, remove the plastic bag and keep the plants in a bright location. Moisten the potting mix as needed. If the seeds do germinate (this is not assured), within three months, the seedlings will develop into viable plants and can be transplanted outdoors after hardening off. After two or three years, they should reach flowering maturity.
Potting and Repotting Gloriosa Lily
Growing gloriosa lily in containers is a good idea for several reasons. First, it’s the only way you can grow it in a cool climate with subzero winters. Second, you avoid the risk that it will spread uncontrolled and become invasive. And lastly, the tubers are very brittle and break easily so the less you are handling them, the better. Therefore, the best option is to plant the tubers in containers where you leave them year-round. In containers, they will need more frequent watering but a sunny patio is usually too hot for the plant. Alternatively, you can bury the containers in garden beds and dig them out again in the fall before the first frost. Use a pot made of any material, but make sure it has drainage holes. Any commercial peat-based potting mix will suffice as a growing medium. Plant the tubers about four inches deep and provide climbing support for the leaf tendrils to cling to as it grows. Keep the soil consistently moist but not wet. Container-grown gloriosa lilies need more frequent feeding (twice a month) than garden-grown plants. It is possible to grow gloriosa lily as a potted indoor houseplant, but it needs a winter dormant period, so you will need to coax it into dormancy by tapering off the watering after the bloom period is done in late fall. Although the plant will appear dead, restoring water in the early spring and giving it plenty of sunlight will bring about the plant’s resurrection.
Overwintering
In regions where the plant is hardy, simply cut back the stems and foliage once the plant begins to turn brown as winter approaches. Potted plants can be moved to a sheltered location for the winter, or indoors if you live in a region with freezing winters. Don’t expect a potted plant to continue active growth indoors over the winter because it requires a winter dormancy period.
Common Pests & Plant Diseases
This plant is often completely trouble-free, but gloriosa lily can occasionally be affected by aphids, anthracnose, cucumber mosaic virus, and other viruses, as well as root rot if grown in soil that is too wet or dense. Aphids can be removed by a strong spray of water or killed with horticultural oil. Anthracnose or viral diseases, signaled by spotted or distorted leaves, are usually fatal, requiring that you throw the plant away.
How to Get Gloriosa Lily to Bloom
Mature gloriosa lily plants will usually bloom robustly from mid-summer into fall provided they are getting plenty of sun and monthly feeding with a diluted fertilizer. The most common reason for bloom failure is a lack of sun, but too little or too much fertilizer can also reduce blooming. Excessive fertilizer can cause the plant to put more energy into foliage growth at the expense of flowers.
Common Problems with Gloriosa Lily
Gloriosa lily is generally a trouble-free plant, but growers are sometimes puzzled and worried if the leaves turn dry and pale. This is not a symptom of disease or pest attack but is usually the result of too much sun exposure in a hot climate. This plant is a sun lover, but it also prefers fairly mild temperatures, and in regions with summer temperatures above 80 degrees Fahrenheit and warm nights, too much sun can cause the leaves to lose their color and dry out. In such regions, try to grow it in a spot that gets plenty of morning sun but is shaded during the warmer afternoon hours.