Thryallis: How To Grow and Care For Galphimia Glauca

Galphimia glauca [gal-FIM-ee-uh, GLOCK-uh] is a member of the Malpighia family and is commonly called Thryallis or Rain of Gold.

The Thryallis plant is a small, perennial evergreen shrub hailing from the tropical areas of Central America and Mexico. 

Blooming Thryallis (Galphimia Glauca)Pin

There, it is very commonly used in folk medicine for a wide variety of ailments, including depression and anxiety.

In its native Mexico, it has several common names, including:

  • Hierba Del Desprecio
  • Hierba Del Cuervo
  • Calderona Amarilla
  • Ojo De Gallina
  • Flor Estrella
  • Kunze

Other common names for this plant are “golden thryallis and the shower of gold plant,” referring to its golden or yellow blossoms.

In other places, the plant is also known by many other common names, such as:

  • Rain of gold plant
  • Goldshower
  • Slender goldshower
  • Spray of gold

Thryallis Quick Care Tips

  • Botanical Name: Thryallis Galphimia Glauca
  • Common Name(s): Rain of Gold, Gold Shower, Shower of Gold
  • Synonyms: Galphimia glauca, Galphimia gracilis, Galphimia heterophylla
  • Family & Origin: Malpighiaceae family, native to Mexico and Central America
  • Growability: Easy to grow
  • Grow Zone: USDA zones 8-9
  • Size: Grows up to 4-6′ feet tall and wide
  • Flowering: Blooms from spring to fall with yellow flowers
  • Light: Full sun to partial shade
  • Humidity: Tolerates low humidity
  • Temperature: Tolerates temperatures down to 30°F
  • Soil: Well-draining soil
  • Water: Water regularly, but do not overwater
  • Fertilizer: Fertilize once a month during the growing season with a balanced fertilizer
  • Pests & Diseases: Susceptible to spider mites and whiteflies, and may develop root rot if overwatered
  • Propagation: Propagated through stem cuttings or by seed
  • Plant Uses: Used as a hedge, border plant, or in containers. The plant has also been used in traditional medicine for its anti-inflammatory properties.

Thryallis Care

Proper care is essential for promoting blooming and maintaining the overall appearance of thryallis shrubs. 

Here are the various aspects you need to consider when growing and caring for the Thryallis or gold shower plant.

Size and Growth

Rain of Gold is a compact, upright evergreen shrub that can grow to be 4′ to 6′ feet tall and spreads to be about 4′ feet wide.

Thyrallis reaches maturity and reaches its full size within a few years of planting. In areas without yearly freezes, it typically reaches a size of 4′ to 6” feet wide and a thryallis height of 5′ to 9′ feet high.

The Thyrallis plant drops its small, green leaves during cold winter months but offers some winter interest in areas with moderate winters thanks to the reddish hue of its stems and branches.

Flowering and Fragrance

In a full sun setting, Flor Estrella is covered with fragrant, sweet-scented yellow flowers from early springtime until the first frost.

Related: For more on Fragrant Garden Flowers

Lack of a full day of sun can cause sparse flowering for this blooming tropical.

The yellow flowers are attractive to hummingbirds, bees, and other pollinators.

Light and Temperature

Although Thryallis plant can tolerate morning shade and afternoon sun, this sun-loving plant performs best in full sun with at least 6 to 8 hours of direct sun each day.

When temperatures drop to 25° degrees Fahrenheit (-4° C), the Thryallis bush will die back to the ground; however, the roots will survive (especially if well mulched before winter commences).

Generally, thryallis blooms during summer and fall, but in the warmer areas of the state, you may enjoy the flowers year-round. When spring arrives, the plant will quickly regrow.

It is winter hardy in USDA hardiness zones 8b through 9. Eye-catching yellow flower clusters wave in the breeze at the end of new shoots. 

So, what’s thryallis cold tolerance?

Thryallis shrubs are not known for their cold tolerance. They do not tolerate cold temperatures well and may suffer damage or even die in freezing conditions.

Thryallis is best suited for warm climates and thrives in USDA Hardiness Zones 9-1.

However, it’s important to note more damage is done to this Golden Thryallis plant by wind than by cold.

Be sure to choose a sheltered setting.

Watering and Feeding

When first planted, you should keep Kunze well watered until it is established.

Once established, this drought-tolerant thryallis shrub requires very little water.

In good quality, well-draining soil, you needn’t fertilize; however, it is a good idea to add organic peat humus and cow manure when you plant golden thryallis seeds or seedlings.

Thryallis glauca is a very good candidate for low-maintenance landscapes. It is very preferable to grow, drought resistant, preferring dry, sandy soil. 

Grooming and Maintenance

Depending on the desired effect, either let this Galphimia glauca plant grow a bit wild throughout most of the growing season or keep it tidily groomed.

Prune the plant to the ground after the first frost and mulch heavily for winter protection. Either way, give it a hard pruning early in the springtime (late March or early April) to get it off to an even start.

For an informal, natural appearance, you might just wish to prune lightly, occasionally during the growing season, to control size.

For a more formal appearance, prune more often to maintain the desired shape and size.

You can even prune thryallis glauca for use as a topiary presentation.

Frequent pruning will result in the loss of flowers.

How To Propagate Galphimia Glauca

Thryallis glauca is a tropical shrub that can be successfully propagated by sowing the seeds while they are still green.

In ideal conditions, the plant will self-sow.

Here are the steps to galphimia gracilis propagation:

  • Alternately, take tender, softwood cuttings during the summertime.
  • Dip the ends of the cuttings in rooting powder and insert them into good-quality, well-draining soil.
  • When the seedlings are about six months old and/or approximately a foot high, they should start to bloom.

Moreover, Galphimia plant can also be propagated by tender softwood cuttings in summer.

Galphimia Glauca Plant Pest or Diseases

When healthy, Ojo De Gallina is virtually pest-free.

It may occasionally be bothered by mites or caterpillars.

Related: Read How To Stop Caterpillars from Eating My Plants.

Thryallis plants are also generally disease-free, but as with any plant, Rain of Gold may experience problems with root rot if it is made to stand in water or overcrowded.

Always use well-draining soil, and space the plants about 3′ to 5′ feet apart.

Is The Thryallis Plant Toxic or Poisonous?

Now, you might wonder, is thryallis poisonous? Or is thryallis toxic to dogs and cats?

There is limited information available about the toxicity of thryallis (Galphimia gracilis).

However, there is no evidence to suggest that thryallis is poisonous to humans or animals. So, Thryallis is generally considered to be a non-toxic plant. 

However, it’s always a good practice to handle all plants with care and wash hands after handling any plant material.

Moreover, it’s important to remember Thryallis bush possesses a wide variety of medicinal properties.

It is used in traditional medicine in Mexico as an antihistamine, an anticonvulsant, an anti-allergic medication, a sedative, and much more.

Kunze contains a wide variety of therapeutic compounds, including phenolics, triterpenoids, and flavonoids.

Current scientific studies are devoted to exploring its use as an anti-inflammatory drug, an antidiarrheal medication, and treatment for a number of other ailments, including malaria and gastroenteritis.

This powerful medicinal plant should not be ingested without proper supervision by an experienced and knowledgeable herbalist and/or a medical doctor.

Are Galphimia Plants Invasive?

Although Golden thryallis grows with wild abandon in its native, very dry settings, this plant is considered exotic outside of Mexico and is not known to be invasive.

Suggested Uses For Thryallis Galphimia Glauca

The Goldenthryallis plant is an attractive, fast-growing plant that makes an excellent privacy hedge, shrub border, or screen in the summer.

It can provide some winter interest in areas with mild winters because of its intricate form, attractive trunks, branches and stems, and persistent fruit.

The Golden thryallis plant makes a nice understory for foundation planting and very tall trees or trees having sparse leaves and tall, plain trunks (e.g., palm trees).

Low-maintenance landscapes use Thryallis glauca for adding height and color to a blank wall along a walk or drive low hedges lining a patio, deck, or porch surrounding the base of palms or tall trees that let enough light through corner-of-the-house accent privacy planting (especially when allowed to grow a bit taller) background plant for shorter shrubs and flowers.

In this sort of setting, Rain of Gold adds a lot of visual interest and can still receive the sun it needs to flower abundantly.

This tall, pretty plant makes a nice backdrop for shorter flowering plants in contrasting colors.

In addition, the Galphimia glauca plant’s loose, open natural growth habit is ideal for informal plantings.

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