American Sweetleaf Plant Care

Andersonglossum virginianum (L.) J.I.Cohen

Updated · Sources · How we source care data

Andersonglossum virginianum, known as southern wild comfrey, is a flowering plant in the borage family native to North America. It is also sometimes called blue houndstongue.

🌱Herbs🌼Perennials🌻Annuals
Water

Every 7–10 days

Light

Partial shade to full sun

Temp

60–75°F

Humidity

40–60%

At a glance

How do you care for American Sweetleaf?

Plant American Sweetleaf in partial shade to full sun (USDA zones 13a) and water a young shrub every 7–10 days until it is established. It tolerates temperatures of 60–75°F (16–24°C). Fertilize it every 6 months during the growing season.

Where Is the American Sweetleaf Native To?

Native range3 countries

What Is the American Sweetleaf?

American Sweetleaf (Andersonglossum virginianum) belongs to the Boraginaceae family within the Andersonglossum genus. American Sweetleaf is native to North America. American Sweetleaf is also known as Virginia Sweetleaf, Wild Sweetleaf.

American Sweetleaf displays a low rosette, spreading ground cover growth habit, reaching up to 0.5 ft tall with a spread of approximately 1 ft. American Sweetleaf produces small bell-shaped flowers in shades of blue, purple, or white.

Leaf size: approximately 3 inches.

How Often Should You Water a American Sweetleaf?

Water a young or newly planted American Sweetleaf 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 American Sweetleaf Need?

American Sweetleaf thrives in partial shade to full sun.

Light Requirement

Partial shade to full sun

What Temperature and Humidity Does the American Sweetleaf Prefer?

Andersonglossum virginianum tolerates temperatures of 60–75°F. American Sweetleaf prefers humidity levels of 40–60%.

Temperature

60–75°F

Humidity

40–60%

What Soil Mix Works Best for a American Sweetleaf?

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

How Often Should You Fertilize a American Sweetleaf?

Feed American Sweetleaf 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 American Sweetleaf?

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

American Sweetleaf 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 American Sweetleaf?

American Sweetleaf can spread to about 1 ft (0.3 m) and reach about 1 ft (0 m) tall. Space plants about 1 ft (0.3 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 American Sweetleaf?

Prune American Sweetleaf 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 American Sweetleaf in Winter?

American Sweetleaf 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 American Sweetleaf?

American Sweetleaf can be propagated through seeds, division of offsets. Similar propagation techniques also apply to wild comfrey plant care, which shares the same genus.

Is the American Sweetleaf Toxic to Pets and Children?

Pet safety not verified

The ASPCA does not list American Sweetleaf, 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 American Sweetleaf?

American Sweetleaf is susceptible to spider mites, aphids, mealybugs. 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 American Sweetleaf Need?

American Sweetleaf grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. American Sweetleaf is native to North America. In cooler regions, grow American Sweetleaf as a houseplant or bring it indoors before the first frost.

Hardiness Zone

Zone 13a

Keep exploring plants

American Sweetleaf 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 Andersonglossum genus — compare its care with other Andersonglossum species on PlantoScan.

Andersonglossum is part of the Boraginaceae plant family — browse all Boraginaceae genera and species.

American Sweetleaf 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: Andersonglossum virginianum (L.) J.I.Cohen, family Boraginaceae (first published in Syst. Bot. 40: 618 (2015)) — World Flora Online record, IPNI name record.
  • Pet toxicity: Pet safety not verified: the ASPCA does not list American Sweetleaf, 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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