Swainsona extrajacens Plant Care

Swainsona extrajacens Joy Thomps.

Updated · Sources · How we source care data

Swainsona extrajacens is a species of flowering plant in the family Fabaceae and is endemic to central Australia. It is an erect, annual plant with imparipinnate leaves with 9 to 21 linear, egg-shaped leaflets, and racemes of purple flowers in racemes of 5 to 10.

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Water

Every 7–10 days

Light

Full sun to partial shade

Temp

50–80°F

Humidity

40–70%

At a glance

How do you care for Swainsona extrajacens?

Plant Swainsona extrajacens in full sun to partial shade (USDA zones 12a) and water a young shrub every 7–10 days until it is established. It tolerates temperatures of 50–80°F (10–27°C). Fertilize it every 6 months during the growing season.

Where Is the Swainsona extrajacens Native To?

Native range1 country

What Is the Swainsona extrajacens?

Swainsona extrajacens (Swainsona extrajacens) belongs to the Fabaceae family within the Swainsona genus. Swainsona extrajacens is native to central Australia.

Swainsona extrajacens displays a bushy perennial shrub growth habit, reaching up to 3 ft tall with a spread of approximately 2 ft. Swainsona extrajacens produces showy pea-like flowers in various colors.

Leaf size: approximately 4 inches.

How Often Should You Water a Swainsona extrajacens?

Water a young or newly planted Swainsona extrajacens 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 Swainsona extrajacens Need?

Swainsona extrajacens thrives in full sun to partial shade.

Light Requirement

Full sun to partial shade

What Temperature and Humidity Does the Swainsona extrajacens Prefer?

Swainsona extrajacens tolerates temperatures of 50–80°F. Swainsona extrajacens prefers humidity levels of 40–70%.

Temperature

50–80°F

Humidity

40–70%

What Soil Mix Works Best for a Swainsona extrajacens?

Well-draining sandy loam with added organic matter. Good drainage is essential for Swainsona extrajacens to prevent waterlogging, which leads to root rot and fungal issues.

How Often Should You Fertilize a Swainsona extrajacens?

Feed Swainsona extrajacens 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 Swainsona extrajacens?

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

Swainsona extrajacens 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 Swainsona extrajacens?

Swainsona extrajacens can spread to about 2 ft (0.6 m) and reach about 3 ft (1 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 Swainsona extrajacens?

Prune Swainsona extrajacens 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 Swainsona extrajacens in Winter?

Swainsona extrajacens 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 Swainsona extrajacens?

Swainsona extrajacens can be propagated through seeds, stem cuttings. Similar propagation techniques also apply to swainsona acuticarinata plant care, which shares the same genus.

Is the Swainsona extrajacens Toxic to Pets and Children?

Pet safety not verified

The ASPCA does not list Swainsona extrajacens, 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 Swainsona extrajacens?

Swainsona extrajacens 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 Swainsona extrajacens Need?

Swainsona extrajacens grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. Swainsona extrajacens is native to central Australia. In cooler regions, grow Swainsona extrajacens as a houseplant or bring it indoors before the first frost.

Hardiness Zone

Zone 12a

Keep exploring plants

Swainsona extrajacens 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 Swainsona genus — compare its care with other Swainsona species on PlantoScan.

Swainsona is part of the Fabaceae plant family — browse all Fabaceae genera and species.

Swainsona extrajacens thrives in bright light and direct sun — see other bright-light plants.

More Swainsona Species

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

Sources

  • Scientific name & taxonomy: Swainsona extrajacens Joy Thomps., family Fabaceae (first published in Telopea 4: 3 (1990)) — World Flora Online record, IPNI name record.
  • Pet toxicity: Pet safety not verified: the ASPCA does not list Swainsona extrajacens, 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 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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