Oval-leaved Mint Bush Plant Care
Prostanthera ovalifolia R.Br.
Updated · Sources · How we source care data
Prostanthera ovalifolia, commonly known as the oval-leaf mintbush or purple mintbush, is a species of flowering plant in the family Lamiaceae and is endemic to south-eastern continental Australia. It is an erect shrub with egg-shaped leaves and groups of mauve to deep blue-purple flowers arranged in groups at the ends of branchlets.
Every 7–14 days
Full sun to partial shade
50–80°F
40–70%
At a glance
How do you care for Oval-leaved Mint Bush?
Plant Oval-leaved Mint Bush in full sun to partial shade (USDA zones 12a) and water a young shrub every 7–14 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 Oval-leaved Mint Bush Native To?
What Is the Oval-leaved Mint Bush?
Oval-leaved Mint Bush (Prostanthera ovalifolia) belongs to the Lamiaceae family within the Prostanthera genus. Oval-leaved Mint Bush is native to south-eastern continental Australia. Oval-leaved Mint Bush is also known as Purple Mint Bush, Round-leaved Mint Bush.
Oval-leaved Mint Bush displays an upright, bushy shrub growth habit, reaching up to 3 ft tall with a spread of approximately 2 ft. Oval-leaved Mint Bush produces small, tubular flowers in shades of purple, pink, or white.
Leaf size: approximately 2 inches.
How Often Should You Water a Oval-leaved Mint Bush?
Water a young or newly planted Oval-leaved Mint Bush every 7–14 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 7–14 days
Until established; then in dry spells
What Light Does the Oval-leaved Mint Bush Need?
Oval-leaved Mint Bush thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Temperature and Humidity Does the Oval-leaved Mint Bush Prefer?
Prostanthera ovalifolia tolerates temperatures of 50–80°F. Oval-leaved Mint Bush prefers humidity levels of 40–70%.
Temperature
50–80°F
Humidity
40–70%
What Soil Mix Works Best for a Oval-leaved Mint Bush?
Well-draining, slightly acidic soil with added organic matter like compost or peat moss. Good drainage is essential for Oval-leaved Mint Bush to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Oval-leaved Mint Bush?
Feed Oval-leaved Mint Bush 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 Oval-leaved Mint Bush?
Choose a spot with full sun to partial shade and well-draining, slightly acidic soil with added organic matter like compost or peat moss. Avoid low spots where water collects after rain.
Oval-leaved Mint Bush 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 Oval-leaved Mint Bush?
Oval-leaved Mint Bush 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 Oval-leaved Mint Bush?
Prune Oval-leaved Mint Bush 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 Oval-leaved Mint Bush in Winter?
Oval-leaved Mint Bush 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 Oval-leaved Mint Bush?
Oval-leaved Mint Bush can be propagated through softwood cuttings, semi-hardwood cuttings. Similar propagation techniques also apply to mint bush plant care, which shares the same genus.
Is the Oval-leaved Mint Bush Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Oval-leaved Mint Bush, 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 Oval-leaved Mint Bush?
Oval-leaved Mint Bush 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 Oval-leaved Mint Bush Need?
Oval-leaved Mint Bush grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. Oval-leaved Mint Bush is native to south-eastern continental Australia. In cooler regions, grow Oval-leaved Mint Bush as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 12a
Keep exploring plants
Oval-leaved Mint Bush 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 Prostanthera genus — compare its care with other Prostanthera species on PlantoScan.
Prostanthera is part of the Lamiaceae plant family — browse all Lamiaceae genera and species.
Oval-leaved Mint Bush thrives in bright light and direct sun — see other bright-light plants.
More Prostanthera Species
Other Prostanthera species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Prostanthera ovalifolia R.Br., family Lamiaceae (first published in Prodr. Fl. Nov. Holland. : 509 (1810)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Oval-leaved Mint Bush, 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.
