Rottboellia cochinchinensis Plant Care
Rottboellia purpurascens Robyns
Updated · Sources · How we source care data
This plant is known for its unique purple-colored grass blades, making it stand out in any garden. Originating from Africa, Rottboellia purpurascens is sought after by plant collectors for its striking appearance and ability to add a pop of color to landscapes.
Every 3–5 days
Full sun
65–85°F
40–70%
At a glance
How do you care for Rottboellia cochinchinensis?
Water Rottboellia cochinchinensis every 3–5 days, letting the top layer of soil dry out between waterings, and give it full sun. It prefers temperatures of 65–85°F (18–29°C) and 40–70% humidity. Fertilize it every 8 months during the growing season.
Where Is the Rottboellia cochinchinensis Native To?
What Is the Rottboellia cochinchinensis?
Rottboellia cochinchinensis (Rottboellia purpurascens) belongs to the Poaceae family within the Rottboellia genus. Rottboellia cochinchinensis is native to tropical Western Africa and the Congo Basin. Rottboellia cochinchinensis is also known as itchgrass.
Rottboellia cochinchinensis displays a tall, spreading grass growth habit, reaching up to 6 ft tall with a spread of approximately 3 ft. Rottboellia cochinchinensis produces small inconspicuous flowers on tall spikes.
Leaf size: approximately 12 inches.
How Often Should You Water a Rottboellia cochinchinensis?
Rottboellia purpurascens requires watering every 3–5 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 3–5 days
Let soil partially dry between waterings
What Light Does the Rottboellia cochinchinensis Need?
Rottboellia cochinchinensis thrives in full sun.
Light Requirement
Full sun
What Temperature and Humidity Does the Rottboellia cochinchinensis Prefer?
Rottboellia purpurascens grows best at temperatures of 65–85°F. Rottboellia cochinchinensis prefers humidity levels of 40–70%.
Temperature
65–85°F
Humidity
40–70%
What Soil Mix Works Best for a Rottboellia cochinchinensis?
Well-draining sandy loam with good organic content. Good drainage is essential for Rottboellia cochinchinensis to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Rottboellia cochinchinensis?
Feed Rottboellia cochinchinensis every 8 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 8 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 Rottboellia cochinchinensis?
Repot every 1-2 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 Rottboellia cochinchinensis?
Rottboellia cochinchinensis can be propagated through division, seeds. Similar propagation techniques also apply to rottboellia campestris plant care, which shares the same genus.
Is the Rottboellia cochinchinensis Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Rottboellia cochinchinensis, 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 Rottboellia cochinchinensis?
Rottboellia cochinchinensis is susceptible to grasshoppers, aphids, cutworms. 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 Rottboellia cochinchinensis Need?
Rottboellia cochinchinensis grows outdoors in USDA Zone 11a – 12b. It survives winters down to planting zone 11a. Rottboellia cochinchinensis is native to tropical Western Africa and the Congo Basin. In cooler regions, grow Rottboellia cochinchinensis as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 11a – 12b
Keep exploring plants
Rottboellia cochinchinensis 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 Rottboellia genus — compare its care with other Rottboellia species on PlantoScan.
Rottboellia is part of the Poaceae plant family — browse all Poaceae genera and species.
Rottboellia cochinchinensis 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: Rottboellia purpurascens Robyns, family Poaceae (first published in Fl. Agrost. Congo Belge 1: 66 (1929)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Rottboellia cochinchinensis, 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 11a – 12b, estimated from the plant's typical growing conditions.
- 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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