Scarlet River Lily Plant Care
Hesperantha coccinea (Backh. & Harv.) Goldblatt & J.C.Manning
Updated · Sources · How we source care data
Hesperantha coccinea, the river lily, or crimson flag lily, synonym Schizostylis coccinea, is a species of flowering plant in the iris family Iridaceae, native to Southern Africa and Zimbabwe. It is a semievergreen perennial growing to 60 cm (24 in) tall, with slender lanceolate leaves up to 40 cm (16 in) long and 1 cm (0.4 in) broad.
Every 7–10 days
Full sun to partial shade
50–80°F
40–70%
At a glance
How do you care for Scarlet River Lily?
Water Scarlet River Lily every 7–10 days, letting the top layer of soil dry out between waterings, and give it full sun to partial shade. It prefers temperatures of 50–80°F (10–27°C) and 40–70% humidity. Fertilize it every 6 months during the growing season.
Where Is the Scarlet River Lily Native To?
What Is the Scarlet River Lily?
Scarlet River Lily (Hesperantha coccinea) belongs to the Iridaceae family within the Hesperantha genus. Scarlet River Lily is native to Southern Africa and Zimbabwe. Scarlet River Lily is also known as Crimson River Lily.
Scarlet River Lily displays a clumping perennial herb growth habit, reaching up to 1.5 ft tall with a spread of approximately 1 ft. Scarlet River Lily produces showy flowers in shades of pink, red, or white.
Leaf size: approximately 12 inches.
How Often Should You Water a Scarlet River Lily?
Hesperantha coccinea requires watering every 7–10 days. Allow the top layer of soil to dry between waterings to prevent root rot. Reduce watering frequency during winter when growth slows.
Watering Frequency
Every 7–10 days
Let soil partially dry between waterings
What Light Does the Scarlet River Lily Need?
Scarlet River Lily thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Temperature and Humidity Does the Scarlet River Lily Prefer?
Hesperantha coccinea grows best at temperatures of 50–80°F. Scarlet River Lily prefers humidity levels of 40–70%.
Temperature
50–80°F
Humidity
40–70%
What Soil Mix Works Best for a Scarlet River Lily?
Well-draining sandy loam with added organic matter. Good drainage is essential for Scarlet River Lily to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Scarlet River Lily?
Feed Scarlet River Lily every 6 months during the growing season (spring and summer) with a balanced fertilizer diluted to the strength on the label.
Pause feeding in autumn and winter, when growth slows, and never fertilize dry soil — water first.
Fertilizing
Every 6 months
During the growing season
The PlantoScan app can remind you when to water and when to fertilize each plant.
How Do You Repot a Scarlet River Lily?
Repot every 2-3 years in early spring. Choose a pot one size larger than the current container, and ensure it has drainage holes to allow excess water to escape.
How Do You Propagate a Scarlet River Lily?
Scarlet River Lily can be propagated through division of rhizomes, seeds.
Is the Scarlet River Lily Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Scarlet River Lily, so we can't confirm whether it is safe for cats and dogs. Keep pets from chewing it as a precaution.
This is a general caution, not veterinary or medical advice. If your pet ate a plant, contact your vet or animal poison control.
See all plants toxic to cats and plants toxic to dogs.
What Pests and Diseases Affect the Scarlet River Lily?
Scarlet River Lily is susceptible to aphids, thrips, spider mites. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.
Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.
What USDA Hardiness Zone Does the Scarlet River Lily Need?
Scarlet River Lily grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. Scarlet River Lily is native to Southern Africa and Zimbabwe. In cooler regions, grow Scarlet River Lily as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 12a
Keep exploring plants
Scarlet River Lily is one of many species covered in the complete plant care and identification guide, which groups plants by genus, attribute, and popularity.
It belongs to the Hesperantha genus — compare its care with other Hesperantha species on PlantoScan.
Hesperantha is part of the Iridaceae plant family — browse all Iridaceae genera and species.
Scarlet River Lily thrives in bright light and direct sun — see other bright-light plants.
Related Plant Care Guides
Closely related plants with similar care requirements:
Sources
- Scientific name & taxonomy: Hesperantha coccinea (Backh. & Harv.) Goldblatt & J.C.Manning, family Iridaceae (first published in Novon 6: 263 (1996)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Scarlet River Lily, so we can't confirm whether it is safe for cats and dogs. Checked against the ASPCA plant list; any other toxicity note on this page comes from PlantoScan's plant database.
- Hardiness zone: USDA Zone 12a, calculated from the plant's minimum temperature.
- Care values(watering, light, temperature, humidity, soil, fertilizing): PlantoScan's plant database, filtered by automatic plausibility checks — values that fail them are hidden. How we source and check plant data.
Spotted a mistake? Email info@upvision.media with the page link — we check and correct reported errors.
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