Large evening primrose Plant Care
Oenothera grandis Smyth
Updated · Sources · How we source care data
Oenothera grandis, variously showy ragged evening-primrose, grand evening primrose, or large-flowered cut-leaved evening primrose, is an annual plant that is native to the southern Great Plains and parts of Mexico.
Every 7–10 days
Full sun to partial shade
60–80°F
40–70%
At a glance
How do you care for Large evening primrose?
Water Large evening primrose 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 60–80°F (16–27°C) and 40–70% humidity. Fertilize it every 6 months during the growing season.
Where Is the Large evening primrose Native To?
What Is the Large evening primrose?
Large evening primrose (Oenothera grandis) belongs to the Onagraceae family within the Oenothera genus. Large evening primrose is native to the southern Great Plains and parts of Mexico.
Large evening primrose displays an upright, clumping perennial growth habit, reaching up to 3 ft tall with a spread of approximately 2 ft. Large evening primrose produces large, showy yellow or pink blooms that open in the evening.
Leaf size: approximately 4 inches.
How Often Should You Water a Large evening primrose?
Oenothera grandis 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 Large evening primrose Need?
Large evening primrose thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Temperature and Humidity Does the Large evening primrose Prefer?
Oenothera grandis grows best at temperatures of 60–80°F. Large evening primrose prefers humidity levels of 40–70%.
Temperature
60–80°F
Humidity
40–70%
What Soil Mix Works Best for a Large evening primrose?
Well-draining, sandy soil with a neutral pH. Good drainage is essential for Large evening primrose to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Large evening primrose?
Feed Large evening primrose 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 Large evening primrose?
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 Large evening primrose?
Large evening primrose can be propagated through seeds, division of root ball. Similar propagation techniques also apply to common evening primrose plant care, which shares the same genus.
Is the Large evening primrose Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Large evening primrose, 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 Large evening primrose?
Large evening primrose is susceptible to aphids, caterpillars, 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 Large evening primrose Need?
Large evening primrose grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. Large evening primrose is native to the southern Great Plains and parts of Mexico. In cooler regions, grow Large evening primrose as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 13a
Keep exploring plants
Large evening primrose 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 Oenothera genus — compare its care with other Oenothera species on PlantoScan.
Oenothera is part of the Onagraceae plant family — browse all Onagraceae genera and species.
Large evening primrose thrives in bright light and direct sun — see other bright-light plants.
More Oenothera Species
Other Oenothera species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Oenothera grandis Smyth, family Onagraceae (first published in Trans. Kansas Acad. Sci. 16: 160 (1899)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Large evening primrose, 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 13a, 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.
Identify Plants Like the
Large evening primrose Instantly
Scan any plant with your phone camera and get instant ID, care tips, water and fertilizer reminders, and health checks — all in one app.
Free
to download
iOS & Android
platforms
Light & dark
mode
100,000+
species