Hoary Mountain Mint Plant Care
Pycnanthemum incanum Michx.
Updated · Sources · How we source care data
Pycnanthemum incanum, with the common name hoary mountainmint, "mountain mint", wild basil or hoary basil, is a herbaceous perennial in the mint family.
Every 7–10 days
Full sun to partial shade
60–80°F
40–70%
At a glance
How do you care for Hoary Mountain Mint?
Water Hoary Mountain Mint 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 40–70% humidity. Fertilize it every 6 months during the growing season.
What Is the Hoary Mountain Mint?
Hoary Mountain Mint (Pycnanthemum incanum) belongs to the Lamiaceae family within the Pycnanthemum genus. Hoary Mountain Mint is also known as Gray Mountain Mint.
Hoary Mountain Mint displays an upright, bushy perennial growth habit, reaching up to 2 ft tall with a spread of approximately 1.5 ft. Hoary Mountain Mint produces clusters of small, tubular white or lavender flowers.
Leaf size: approximately 3 inches.
How Often Should You Water a Hoary Mountain Mint?
Pycnanthemum incanum 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 Hoary Mountain Mint Need?
Hoary Mountain Mint thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Temperature and Humidity Does the Hoary Mountain Mint Prefer?
Pycnanthemum incanum grows best at temperatures of 60–80°F. Hoary Mountain Mint prefers humidity levels of 40–70%.
Temperature
60–80°F
Humidity
40–70%
What Soil Mix Works Best for a Hoary Mountain Mint?
Well-draining sandy loam with added organic matter for moisture retention. Good drainage is essential for Hoary Mountain Mint to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Hoary Mountain Mint?
Feed Hoary Mountain Mint 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 Hoary Mountain Mint?
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 Hoary Mountain Mint?
Hoary Mountain Mint can be propagated through seeds, division of clumps. Similar propagation techniques also apply to slender mountain mint plant care, which shares the same genus.
Is the Hoary Mountain Mint Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Hoary Mountain Mint, 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 Hoary Mountain Mint?
Hoary Mountain Mint 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 Hoary Mountain Mint Need?
Hoary Mountain Mint grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. In cooler regions, grow Hoary Mountain Mint as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 13a
Keep exploring plants
Hoary Mountain Mint 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 Pycnanthemum genus — compare its care with other Pycnanthemum species on PlantoScan.
Pycnanthemum is part of the Lamiaceae plant family — browse all Lamiaceae genera and species.
Hoary Mountain Mint thrives in bright light and direct sun — see other bright-light plants.
More Pycnanthemum Species
Other Pycnanthemum species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Pycnanthemum incanum Michx., family Lamiaceae (first published in Fl. Bor.-Amer. 2: 7 (1803)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Hoary Mountain Mint, 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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