Photo: BogdanCC BY-SA 3.0via Wikimedia Commonsresized / cropped
Cottonbush Plant Care
Tetradymia argyraea Munz & J.C.Roos
Updated · Sources · How we source care data
Tetradymia argyraea is a species of flowering plant in the aster family known by the common names striped cottonthorn and striped horsebrush. It is native to the desert mountains of the southwestern United States, particularly of California, Nevada, and Arizona, where it grows in desert woodland habitat. It is a woolly, spiny shrub growing one half to nearly two meters in maximum height. The erect stems are white-woolly except for bare stripes at intervals. The leaves are linear in shape and harden as they age, becoming spiny. The larger leaves are woolly and there are clusters of smaller, threadlike leaves which may be hairless. The inflorescence bears two to five flower heads which are each enveloped in five thick phyllaries coated in white woolly hairs. Each head contains five pale yellow flowers each around a centimeter long. Flowers are produced in summer, as late as September. The fruit is an achene a few millimeters long tipped with a pappus of bristles.
Every 14–21 days
Full sun
50–85°F
20–60%
At a glance
How do you care for Cottonbush?
Plant Cottonbush in full sun (USDA zones 12a) and water a young shrub every 14–21 days until it is established. It tolerates temperatures of 50–85°F (10–29°C).
Where Is the Cottonbush Native To?
What Is the Cottonbush?
Cottonbush (Tetradymia argyraea) belongs to the Asteraceae family within the Tetradymia genus. Cottonbush is native to the desert mountains of the southwestern United States, particularly of California, Nevada, and Arizona. Cottonbush is also known as Tetradymia argyraea.
Cottonbush displays a low, spreading shrub growth habit, reaching up to 2 ft tall with a spread of approximately 4 ft. Cottonbush produces small yellow flowers in clusters.
Leaf size: approximately 1.5 inches.
How Often Should You Water a Cottonbush?
Water a young or newly planted Cottonbush every 14–21 days, soaking the whole root zone, until it is established — usually one to two growing seasons. Established shrubs mainly need water during long dry spells. In a container, water whenever the top few centimetres of soil are dry.
Watering Frequency
Every 14–21 days
Until established; then in dry spells
What Light Does the Cottonbush Need?
Cottonbush thrives in full sun.
Light Requirement
Full sun
What Temperature and Humidity Does the Cottonbush Prefer?
Tetradymia argyraea tolerates temperatures of 50–85°F. Cottonbush prefers humidity levels of 20–60%.
Temperature
50–85°F
Humidity
20–60%
What Soil Mix Works Best for a Cottonbush?
Well-draining sandy soil with low fertility. Good drainage is essential for Cottonbush to prevent waterlogging, which leads to root rot and fungal issues.
Where Should You Plant a Cottonbush?
Choose a spot with full sun and well-draining sandy soil with low fertility. Avoid low spots where water collects after rain.
Cottonbush is suited to USDA Zone 12a.
Plant container-grown or balled-and-burlapped shrubs in spring or early autumn, setting the root flare at soil level, and water well after planting.
How Far Apart Should You Plant a Cottonbush?
Cottonbush can spread to about 4 ft (1.2 m) and reach about 2 ft (1 m) tall. Space plants about 4 ft (1.2 m) apart so mature crowns don't crowd each other, and plant at least half that distance from buildings, fences and paths.
Planning a row or hedge? Try the plant spacing calculator.
How Do You Prune a Cottonbush?
Prune Cottonbush while it is dormant in late winter: first remove dead, damaged and crossing branches, then thin lightly for shape.
If it flowers in spring, prune right after flowering instead so you don't remove next year's buds. Never take off more than about a quarter of the shrub in one year.
How Do You Care for a Cottonbush in Winter?
Cottonbush is frost-tender (hardy to USDA zone 12). In colder areas grow it in a container and move it to a bright, frost-free place before the first frost.
How Do You Propagate a Cottonbush?
Cottonbush can be propagated through seeds. Similar propagation techniques also apply to spineless horsebrush plant care, which shares the same genus.
Is the Cottonbush Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Cottonbush, 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 Cottonbush?
Cottonbush is susceptible to aphids, 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 Cottonbush Need?
Cottonbush grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. Cottonbush is native to the desert mountains of the southwestern United States, particularly of California, Nevada, and Arizona. In cooler regions, grow Cottonbush as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 12a
Keep exploring plants
Cottonbush 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 Tetradymia genus — compare its care with other Tetradymia species on PlantoScan.
Tetradymia is part of the Asteraceae plant family — browse all Asteraceae genera and species.
Cottonbush thrives in bright light and direct sun — see other bright-light plants.
More Tetradymia Species
Other Tetradymia species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Tetradymia argyraea Munz & J.C.Roos, family Asteraceae (first published in Aliso 2: 237 (1950)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Cottonbush, 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: Bogdan, CC BY-SA 3.0, 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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