Photo: HermannSchachnerCC0via Wikimedia Commons
Purple Lettuce Plant Care
Prenanthes purpurea L.
Updated · Sources · How we source care data
Prenanthes is a genus of plant in the family Asteraceae, often referred to as rattlesnake root.
Every 7–10 days
Partial shade to full sun
50–75°F
40–70%
At a glance
How do you care for Purple Lettuce?
Water Purple Lettuce every 7–10 days, letting the top layer of soil dry out between waterings, and give it partial shade to full sun. It prefers temperatures of 50–75°F (10–24°C) and 40–70% humidity. Fertilize it every 6 months during the growing season.
What Is the Purple Lettuce?
Purple Lettuce (Prenanthes purpurea) belongs to the Asteraceae family within the Prenanthes genus. Purple Lettuce is also known as Purple Wall Lettuce, Purple Viper's Grass, Chondrilla purpurea.
Purple Lettuce displays an upright, clumping perennial growth habit, reaching up to 2 ft tall with a spread of approximately 1.5 ft. Purple Lettuce produces small white or yellow clustered flowers in late summer.
Leaf size: approximately 4 inches.
How Often Should You Water a Purple Lettuce?
Prenanthes purpurea 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 Purple Lettuce Need?
Purple Lettuce thrives in partial shade to full sun.
Light Requirement
Partial shade to full sun
What Temperature and Humidity Does the Purple Lettuce Prefer?
Prenanthes purpurea grows best at temperatures of 50–75°F. Purple Lettuce prefers humidity levels of 40–70%.
Temperature
50–75°F
Humidity
40–70%
What Soil Mix Works Best for a Purple Lettuce?
Well-draining loamy soil with added organic matter for moisture retention. Good drainage is essential for Purple Lettuce to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Purple Lettuce?
Feed Purple Lettuce 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 Purple Lettuce?
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 Purple Lettuce?
Purple Lettuce can be propagated through seeds, division of rhizomes.
Is the Purple Lettuce Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Purple Lettuce, 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 Purple Lettuce?
Purple Lettuce is susceptible to aphids, slugs, snails. 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 Purple Lettuce Need?
Purple Lettuce grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. In cooler regions, grow Purple Lettuce as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 12a
Keep exploring plants
Purple Lettuce 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 Prenanthes genus — compare its care with other Prenanthes species on PlantoScan.
Prenanthes is part of the Asteraceae plant family — browse all Asteraceae genera and species.
Purple Lettuce 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: Prenanthes purpurea L., family Asteraceae (first published in Sp. Pl. : 797 (1753)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Purple Lettuce, 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.
- Photo: HermannSchachner, CC0, Wikimedia Commons — original.
- 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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