Detonated Hazardia (Hazardia detonsa)

Photo: StickpenPublic domainvia Wikimedia Commons

Detonated Hazardia Plant Care

Hazardia detonsa Greene

Updated · Sources · How we source care data

Hazardia detonsa is a rare species of shrub in the family Asteraceae known by the common name island bristleweed. It is endemic to the Channel Islands of California, having been found on 4 islands (Santa Rosa, Santa Cruz, West Anacapa, and Middle Anacapa).

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Water

Every 7–10 days

Light

Full sun to partial shade

Temp

60–80°F

Humidity

40–60%

At a glance

How do you care for Detonated Hazardia?

Plant Detonated Hazardia in full sun to partial shade (USDA zones 13a) and water a young shrub every 7–10 days until it is established. It tolerates temperatures of 60–80°F (16–27°C). Fertilize it every 6 months during the growing season.

Where Is the Detonated Hazardia Native To?

Native range1 country

What Is the Detonated Hazardia?

Detonated Hazardia (Hazardia detonsa) belongs to the Asteraceae family within the Hazardia genus. Detonated Hazardia is native to the Channel Islands of California. Detonated Hazardia is also known as Corethrogyne detonsa, Haplopappus detonsus.

Detonated Hazardia displays a low spreading shrub growth habit, reaching up to 1.5 ft tall with a spread of approximately 2 ft. Detonated Hazardia produces small daisy-like flowers in various colors.

Leaf size: approximately 3 inches.

How Often Should You Water a Detonated Hazardia?

Water a young or newly planted Detonated Hazardia every 7–10 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 7–10 days

Until established; then in dry spells

What Light Does the Detonated Hazardia Need?

Detonated Hazardia thrives in full sun to partial shade.

Light Requirement

Full sun to partial shade

What Temperature and Humidity Does the Detonated Hazardia Prefer?

Hazardia detonsa tolerates temperatures of 60–80°F. Detonated Hazardia prefers humidity levels of 40–60%.

Temperature

60–80°F

Humidity

40–60%

What Soil Mix Works Best for a Detonated Hazardia?

Well-draining sandy soil mix with some organic matter. Good drainage is essential for Detonated Hazardia to prevent waterlogging, which leads to root rot and fungal issues.

How Often Should You Fertilize a Detonated Hazardia?

Feed Detonated Hazardia every 6 months during the growing season with a balanced, slow-release fertilizer at the rate on the label. Established shrubs in good soil often need little extra feeding, so let weak growth or pale foliage guide you.

Stop feeding by late summer so new growth can harden before winter.

Fertilizing

Every 6 months

During the growing season

The PlantoScan app can remind you when to water and when to fertilize each plant.

Where Should You Plant a Detonated Hazardia?

Choose a spot with full sun to partial shade and well-draining sandy soil mix with some organic matter. Avoid low spots where water collects after rain.

Detonated Hazardia is suited to USDA Zone 13a.

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 Detonated Hazardia?

Detonated Hazardia can spread to about 2 ft (0.6 m) and reach about 2 ft (0 m) tall. Space plants about 2 ft (0.6 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 Detonated Hazardia?

Prune Detonated Hazardia 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 Detonated Hazardia in Winter?

Detonated Hazardia is frost-tender (hardy to USDA zone 13). 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 Detonated Hazardia?

Detonated Hazardia can be propagated through seeds, stem cuttings. Similar propagation techniques also apply to berberis hazardia plant care, which shares the same genus.

Is the Detonated Hazardia Toxic to Pets and Children?

Pet safety not verified

The ASPCA does not list Detonated Hazardia, 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 Detonated Hazardia?

Detonated Hazardia is susceptible to aphids, whiteflies, 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 Detonated Hazardia Need?

Detonated Hazardia grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. Detonated Hazardia is native to the Channel Islands of California. In cooler regions, grow Detonated Hazardia as a houseplant or bring it indoors before the first frost.

Hardiness Zone

Zone 13a

Keep exploring plants

Detonated Hazardia 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 Hazardia genus — compare its care with other Hazardia species on PlantoScan.

Hazardia is part of the Asteraceae plant family — browse all Asteraceae genera and species.

Detonated Hazardia thrives in bright light and direct sun — see other bright-light plants.

More Hazardia Species

Other Hazardia species in PlantoScan's care catalogue share similar watering, light, and soil preferences:

Sources

  • Scientific name & taxonomy: Hazardia detonsa Greene, family Asteraceae (first published in Pittonia 1(1): 29 (1887)) — World Flora Online record, IPNI name record.
  • Pet toxicity: Pet safety not verified: the ASPCA does not list Detonated Hazardia, 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: Stickpen, Public domain, Wikimedia Commons — original.
  • 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.

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