Wedgeleaf Milk Vetch Plant Care

Astragalus amphioxys A.Gray

Updated · Sources · How we source care data

Astragalus amphioxys, common name crescent milkvetch, is a plant found in the American southwest, including the whole of Utah, the southeast part of Nevada, the north part of Arizona, the western part of Colorado, the northwestern part of New Mexico, and one county in Texas. It was first described by Asa Gray in 1878.

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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 Wedgeleaf Milk Vetch?

Plant Wedgeleaf Milk Vetch 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 8 months during the growing season.

Where Is the Wedgeleaf Milk Vetch Native To?

Native range1 country

What Is the Wedgeleaf Milk Vetch?

Wedgeleaf Milk Vetch (Astragalus amphioxys) belongs to the Fabaceae family within the Astragalus genus. Wedgeleaf Milk Vetch is native to the American southwest, including the whole of Utah, the southeast part of Nevada, the north part of Arizona, the western part of Colorado, the northwestern part of New Mexico, and one county in Texas. Wedgeleaf Milk Vetch is also known as Desert Milk Vetch.

Wedgeleaf Milk Vetch displays a low spreading ground cover growth habit, reaching up to 0.5 ft tall with a spread of approximately 2 ft. Wedgeleaf Milk Vetch produces small pea-like flowers in shades of purple, pink, or white.

Leaf size: approximately 1 inches.

How Often Should You Water a Wedgeleaf Milk Vetch?

Water a young or newly planted Wedgeleaf Milk Vetch 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 Wedgeleaf Milk Vetch Need?

Wedgeleaf Milk Vetch thrives in full sun to partial shade.

Light Requirement

Full sun to partial shade

What Temperature and Humidity Does the Wedgeleaf Milk Vetch Prefer?

Astragalus amphioxys tolerates temperatures of 60–80°F. Wedgeleaf Milk Vetch prefers humidity levels of 40–60%.

Temperature

60–80°F

Humidity

40–60%

What Soil Mix Works Best for a Wedgeleaf Milk Vetch?

Well-draining sandy soil mix with added perlite for extra drainage. Good drainage is essential for Wedgeleaf Milk Vetch to prevent waterlogging, which leads to root rot and fungal issues.

How Often Should You Fertilize a Wedgeleaf Milk Vetch?

Feed Wedgeleaf Milk Vetch every 8 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 8 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 Wedgeleaf Milk Vetch?

Choose a spot with full sun to partial shade and well-draining sandy soil mix with added perlite for extra drainage. Avoid low spots where water collects after rain.

Wedgeleaf Milk Vetch 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 Wedgeleaf Milk Vetch?

Wedgeleaf Milk Vetch can spread to about 2 ft (0.6 m) and reach about 1 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 Wedgeleaf Milk Vetch?

Prune Wedgeleaf Milk Vetch 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 Wedgeleaf Milk Vetch in Winter?

Wedgeleaf Milk Vetch 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 Wedgeleaf Milk Vetch?

Wedgeleaf Milk Vetch can be propagated through seeds, division of root ball. Similar propagation techniques also apply to aragallus acutirostris plant care, which shares the same genus.

Is the Wedgeleaf Milk Vetch Toxic to Pets and Children?

Pet safety not verified

The ASPCA does not list Wedgeleaf Milk Vetch, 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 Wedgeleaf Milk Vetch?

Wedgeleaf Milk Vetch is susceptible to aphids, spider mites, leafhoppers. 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 Wedgeleaf Milk Vetch Need?

Wedgeleaf Milk Vetch grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. Wedgeleaf Milk Vetch is native to the American southwest, including the whole of Utah, the southeast part of Nevada, the north part of Arizona, the western part of Colorado, the northwestern part of New Mexico, and one county in Texas. In cooler regions, grow Wedgeleaf Milk Vetch as a houseplant or bring it indoors before the first frost.

Hardiness Zone

Zone 13a

Keep exploring plants

Wedgeleaf Milk Vetch 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 Astragalus genus — compare its care with other Astragalus species on PlantoScan.

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

Wedgeleaf Milk Vetch thrives in bright light and direct sun — see other bright-light plants.

More Astragalus Species

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

Sources

  • Scientific name & taxonomy: Astragalus amphioxys A.Gray, family Fabaceae — World Flora Online record, IPNI name record.
  • Pet toxicity: Pet safety not verified: the ASPCA does not list Wedgeleaf Milk Vetch, 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.

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