Pennyroyal Mentha pulegium 'Upright'

☠ Toxic to humans
🐾 Toxic to pets
🌸 Not blooming
🍪 Edible
‍🌱 Easy-care
pennyroyal 'Upright'


The plant known as 'Upright' pennyroyal features a robust and erect growth habit, setting it apart from the more common sprawling type. Its foliage is characteristically vibrant green with a somewhat ovate to oblong shape, marked by small indentations along the edges which are known as serrations, giving the leaves a slightly ragged appearance. The leaves emanate a strong, minty fragrance when crushed or even brushed against, which is quite characteristic of the pennyroyal variety. During its blooming season, 'Upright' pennyroyal produces clusters of lilac to violet flowers, which are small and tubular, typically arranged in dense whorls around the stem. These flowers are not only aesthetic, attracting pollinators such as bees and butterflies, but also contribute to the plant's overall ornamental appeal. The stems of the plant are square in cross-section, which is typical of members of the mint family, and they sometimes bear a purplish hue, particularly near the flowering tips. Overall, 'Upright' pennyroyal has a compact and tidy appearance, with its upright stems densely clothed in leaves, making it a popular choice for gardeners who wish to incorporate aromatic and culinary herbs into their spaces. Despite avoiding mention of its size, it's significant to understand that this plant's visual impact is relative to its growth habit, which is more vertical compared to the traditional sprawling pennyroyal.

Plant Info
Common Problems

About this plant

  • memoNames

    • Synonyms

      Pennyroyal, European Pennyroyal, Squaw Mint, Mosquito Plant, Pudding Grass.

    • Common names

      Mentha pulegium.

  • infoCharacteristics

    • Life cycle


    • Foliage type


    • Color of leaves


    • Flower color


    • Height

      1 foot (30 cm)

    • Spread

      1 foot (30 cm)

    • Plant type


    • Hardiness zones


    • Native area



  • money-bagGeneral Benefits

    • Aromatic Properties: Emits a pleasant fragrance which can be enjoyed in a garden setting.
    • Culinary Uses: Leaves can be used to flavor a wide range of dishes and beverages.
    • Insect Repellent: Known to naturally repel certain insects, helping to keep them away from outdoor living spaces.
    • Garden Aesthetics: Provides lush greenery and can be used to create visually appealing borders or ground cover.
    • Easy to Grow: Tolerates a variety of soil types and conditions, making it suitable for many gardeners.
    • Low Maintenance: Requires minimal care once established, with moderate watering and occasional pruning.

  • medicalMedical Properties

    • Antispasmodic: Pennyroyal (Mentha pulegium 'Upright') has historically been used for its antispasmodic properties to relieve muscle spasms and cramps.
    • Emmenagogue: Traditionally believed to stimulate menstrual flow and alleviate menstrual cramps.
    • Carminative: May help to relieve digestive issues such as indigestion and gas.
    • Insect Repellant: Essential oil can be used as a natural insect repellent against mosquitoes and other insects.

  • windAir-purifying Qualities

    This plant is not specifically known for air purifying qualities.

  • leavesOther Uses

    • Mentha pulegium, commonly known as pennyroyal, can be used as an insect repellent in gardens to protect other plants from pest infestations.
    • It is sometimes incorporated into potpourri and scented sachets for its strong minty fragrance.
    • Pennyroyal can be used in small quantities to flavor some traditional dishes, though it must be used with caution due to its potent constituents.
    • The oil can be applied to the skin of pets to act as a flea repellent, but care must be taken due to potential toxicity.
    • Dried pennyroyal leaves can be used to repel rodents when placed in areas where these pests are not welcome.
    • The plant has been used historically to stuff mattresses and pillows to deter insects during sleep.
    • In small amounts, pennyroyal has been used to flavor teas, although it must be used with extreme caution.
    • Some people use the leaves in their wardrobes or among linens to prevent mustiness and to keep moths away from textiles.
    • Pennyroyal can be planted in chicken coops to deter pests from bothering poultry.
    • The strong scent of pennyroyal has been used in natural homemade cleaning solutions for disinfecting surfaces.

Interesting Facts

  • bedFeng Shui

    Pennyroyal is not used in Feng Shui practice.

  • aquariusZodiac Sign Compitability

    Pennyroyal is not used in astrology practice.

  • spiralPlant Symbolism

    • Protection: Mint plants, including Mentha pulegium 'Upright', commonly known as Pennyroyal, are often associated with protective properties in folklore, believed to ward off evil spirits and harmful entities.
    • Strength: The robust and invasive nature of Pennyroyal symbolizes strength and resilience, reflecting its ability to thrive in various conditions.
    • Cleansing: Due to its fresh, pungent aroma, Pennyroyal has been used in various cultures for purification rituals, symbolizing the cleansing of spaces and the spirit.
    • Healing: Pennyroyal has medicinal properties and has been used traditionally to alleviate various ailments, representing healing and relief from physical and emotional pain.

Every 1-2 weeks
2500 - 10000 Lux
Every 1-2 years
As needed
  • water dropWater

    Pennyroyal, also known as Mentha pulegium, should be watered deeply but infrequently to ensure healthy growth. It is best to water when the top inch of soil feels dry to the touch, which typically translates to about once a week. Depending on the weather and soil conditions, you might need to adjust watering frequency. As a guideline, provide the pennyroyal with approximately one gallon of water per week during the growing season. During the winter, reduce watering to every other week unless the soil is still moist from the previous watering.

  • sunLight

    Pennyroyal prefers full to partial sunlight to thrive. The best spot for this plant would be in an area where it can receive at least six hours of direct sunlight a day. When growing indoors, placing pennyroyal near a south or west-facing window would provide suitable light conditions.

  • thermometerTemperature

    Pennyroyal grows best in temperate climates with temperatures ranging from 60 to 70 degrees Fahrenheit. The plant can survive minimum temperatures down to about 30 degrees Fahrenheit, and a maximum of around 80 degrees Fahrenheit. It's ideal to avoid exposure to temperatures outside this range for extended periods to prevent damage to the plant.

  • scissorsPruning

    Pruning pennyroyal is essential for maintaining its shape and encouraging fuller, bushier growth. It should be pruned in early spring, just as new growth starts to appear. Removing dead or leggy branches can be done at any time of the year as needed. Regular trimming of the tips can help to keep the plant compact.

  • broomCleaning

    As needed

  • bambooSoil

    Pennyroyal, commonly known as Mentha pulegium 'Upright', thrives best in a soil mix that is rich in organic matter, with good drainage, and slightly acidic to neutral pH levels, ideally between 6.0 and 7.0. A mix of two parts peat or coco coir, one part perlite or sand, and one part compost or aged manure would provide the necessary nutrients and structure for growth.

  • plantRepotting

    Pennyroyal should be repotted every 2 to 3 years to refresh the soil and accommodate its growth. It can be invasive, so keeping Pennyroyal in containers helps to manage its spread and provides an opportunity to divide the plant during repotting if it becomes too large.

  • water dropsHumidity & Misting

    Pennyroyal requires moderate humidity levels, consistent with what is typically found in the average home or garden environment. It is not particularly demanding but should not be left in extremely dry air for prolonged periods.

  • pinSuitable locations

    • Indoor

      Keep Pennyroyal in bright, indirect light and moist soil.

    • Outdoor

      Plant Pennyroyal in partial shade and moist, well-draining soil.

    • Hardiness zone

      5-9 USDA

  • circleLife cycle

    Mentha pulegium 'Upright', commonly known as pennyroyal, begins its life cycle as a seed which, when sown in warm, moist soil, germinates within 10 to 20 days. Upon sprouting, the seedling grows into a compact, upright herb with a square stem, characteristic of the Lamiaceae family. As the plant matures, it develops fragrant, oval-shaped leaves and blooms in mid to late summer, producing small lavender to purple flowers that attract pollinators. After pollination, the flowers develop into four tiny nutlets that contain seeds for the next generation. In temperate climates, pennyroyal dies back to the ground in winter, but the root system remains alive and the plant regrows in spring. This perennial herb may also propagate vegetatively from cuttings or by natural layering, allowing for expansion of growth or new plant cultivation.

  • sproutPropogation

    • Propogation time


    • Mentha pulegium 'Upright', commonly known as Pennyroyal, is often propagated by stem cuttings. This method is popular due to its simplicity and high success rate. To propagate Pennyroyal using stem cuttings, one should cut a healthy stem from the parent plant, ensuring that it is about 2 to 6 inches (5 to 15 cm) in length, and has several nodes. The lower leaves are removed, and the cut end can be dipped in rooting hormone to encourage root development if desired. The cutting is then placed in a pot with moist potting mix, ensuring that at least one node is buried under the soil where roots can develop. The pot should be kept in a warm, bright area but out of direct sunlight, and the soil should remain consistently moist. Roots often establish within a few weeks, after which the new plant can gradually be acclimated to less-controlled conditions.