Grand Collomia Plant Care
Collomia grandiflora Douglas ex Lindl.
Updated · Sources · How we source care data
Collomia grandiflora is a western North American annual plant in the phlox family (Polemoniaceae), known by the common names grand collomia, large-flowered mountain trumpet, and large-flowered collomia. It usually appears in sandy habitats and is cultivated as an ornamental.
Full sun to partial shade
At a glance
How do you care for Grand Collomia?
Grand Collomia grows best in full sun to partial shade.
What Is the Grand Collomia?
Grand Collomia (Collomia grandiflora) belongs to the Polemoniaceae family within the Collomia genus. Grand Collomia is also known as Largeflower Collomia.
Grand Collomia displays a low rosette, spreading growth habit, reaching up to tall with a spread of approximately . Grand Collomia produces clusters of small tubular flowers in shades of pink, purple, or white.
What Light Does the Grand Collomia Need?
Grand Collomia thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Soil Mix Works Best for a Grand Collomia?
Well-draining sandy loam with added organic matter for moisture retention. Good drainage is essential for Grand Collomia to prevent waterlogging, which leads to root rot and fungal issues.
How Do You Repot a Grand Collomia?
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 Grand Collomia?
Grand Collomia can be propagated through seeds, division of clumps. Similar propagation techniques also apply to collomia diversifolia plant care, which shares the same genus.
Is the Grand Collomia Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Grand Collomia, 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 Grand Collomia?
Grand Collomia is susceptible to aphids, spider mites, whiteflies. 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.
Keep exploring plants
Grand Collomia 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 Collomia genus — compare its care with other Collomia species on PlantoScan.
Collomia is part of the Polemoniaceae plant family — browse all Polemoniaceae genera and species.
Grand Collomia 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: Collomia grandiflora Douglas ex Lindl., family Polemoniaceae (first published in Bot. Reg. 14: t. 1174 (1828)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Grand Collomia, 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.
- 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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