Slenderleaf False Foxglove Plant Care
Agalinis tenuifolia (Vahl) Raf.
Updated · Sources · How we source care data
Agalinis tenuifolia, known by the common names common gerardia, slender false foxglove or common false foxglove, is an annual forb native to the eastern and southwestern United States, and Canada, which produces purple flowers in late summer or early fall.
Every 7–10 days
Full sun to partial shade
60–80°F
40–60%
At a glance
How do you care for Slenderleaf False Foxglove?
Water Slenderleaf False Foxglove every 7–10 days, letting the top layer of soil dry out between waterings, and give it full sun to partial shade. It prefers temperatures of 60–80°F (16–27°C) and 40–60% humidity. Fertilize it every 6 months during the growing season.
Where Is the Slenderleaf False Foxglove Native To?
What Is the Slenderleaf False Foxglove?
Slenderleaf False Foxglove (Agalinis tenuifolia) belongs to the Orobanchaceae family within the Agalinis genus. Slenderleaf False Foxglove is native to the eastern and southwestern United States, and Canada, which produces purple flowers in late summer or early fall. Slenderleaf False Foxglove is also known as Purple False Foxglove, Smallflower False Foxglove.
Slenderleaf False Foxglove displays an upright, branching perennial growth habit, reaching up to 1.5 ft tall with a spread of approximately 1 ft. Slenderleaf False Foxglove produces tubular flowers in shades of pink, purple, or white.
Leaf size: approximately 2 inches.
How Often Should You Water a Slenderleaf False Foxglove?
Agalinis tenuifolia requires watering every 7–10 days. Allow the top layer of soil to dry between waterings to prevent root rot. Reduce watering frequency during winter when growth slows.
Watering Frequency
Every 7–10 days
Let soil partially dry between waterings
What Light Does the Slenderleaf False Foxglove Need?
Slenderleaf False Foxglove thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Temperature and Humidity Does the Slenderleaf False Foxglove Prefer?
Agalinis tenuifolia grows best at temperatures of 60–80°F. Slenderleaf False Foxglove prefers humidity levels of 40–60%.
Temperature
60–80°F
Humidity
40–60%
What Soil Mix Works Best for a Slenderleaf False Foxglove?
Well-draining sandy loam with added organic matter. Good drainage is essential for Slenderleaf False Foxglove to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Slenderleaf False Foxglove?
Feed Slenderleaf False Foxglove every 6 months during the growing season (spring and summer) with a balanced fertilizer diluted to the strength on the label.
Pause feeding in autumn and winter, when growth slows, and never fertilize dry soil — water first.
Fertilizing
Every 6 months
During the growing season
The PlantoScan app can remind you when to water and when to fertilize each plant.
How Do You Repot a Slenderleaf False Foxglove?
Repot every 2-3 years in early spring. Choose a pot one size larger than the current container, and ensure it has drainage holes to allow excess water to escape.
How Do You Propagate a Slenderleaf False Foxglove?
Slenderleaf False Foxglove can be propagated through seeds, division of clumps. Similar propagation techniques also apply to rough false foxglove plant care, which shares the same genus.
Is the Slenderleaf False Foxglove Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Slenderleaf False Foxglove, 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 Slenderleaf False Foxglove?
Slenderleaf False Foxglove is susceptible to aphids, spider mites, whiteflies. 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 Slenderleaf False Foxglove Need?
Slenderleaf False Foxglove grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. Slenderleaf False Foxglove is native to the eastern and southwestern United States, and Canada, which produces purple flowers in late summer or early fall. In cooler regions, grow Slenderleaf False Foxglove as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 13a
Keep exploring plants
Slenderleaf False Foxglove 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 Agalinis genus — compare its care with other Agalinis species on PlantoScan.
Agalinis is part of the Orobanchaceae plant family — browse all Orobanchaceae genera and species.
Slenderleaf False Foxglove thrives in bright light and direct sun — see other bright-light plants.
More Agalinis Species
Other Agalinis species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Agalinis tenuifolia (Vahl) Raf., family Orobanchaceae (first published in New Fl. [Rafinesque] ii. 64 (1836).) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Slenderleaf False Foxglove, 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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