Cup Plant Silphium perfoliatum

👤 Non-toxic to humans
🐾 Non-toxic to pets
🌸 Blooming
🍪 Not edible
‍🌱 Easy-care
cup plant


Cup plant, as it is commonly known, is a perennial native to large parts of North America. It is distinctive for its square-stemmed, sturdy structure and the way its leaves are fused around the stem, forming a cup-like shape that can hold water after rainfalls. The leaves themselves are broad and slightly toothed, providing a contrasting backdrop for the bright yellow flowers that appear in the summer. These flowers, with their sunny, daisy-like appearance, have a central disc surrounded by petal-like rays that attract pollinators. The cup plant's rough texture and tall presence in landscapes make it a noticeable and valuable plant for wildlife, providing both nectar for insects and a water source for birds.

Plant Info
Common Problems

About this plant

  • memoNames

    • Family


    • Synonyms

      Cup Plant, Indian Cup, Squareweed, Carpenter's Weed.

    • Common names

      Silphium connatum, Silphium perfoliatum var. connatum, Phlomis perfoliata, Silphium laciniatum var. robinsonii.

  • skullToxicity

    • To humans

      Cup plant (Silphium perfoliatum) is generally not considered toxic to humans. There are no widespread reports of poisoning or adverse effects from ingesting this plant. However, as with any plant material, individual sensitivities can vary, and it is always prudent to exercise caution and avoid ingesting plants not meant for human consumption without proper knowledge or guidance.

    • To pets

      Cup plant (Silphium perfoliatum) is not known to be toxic to pets such as dogs and cats. There is no evidence to suggest that pets suffer from poisoning upon ingesting this plant. As with any non-food plant, ingestion in large amounts could potentially cause mild gastrointestinal upset due to the novelty of the material, but no specific toxic symptoms are associated with this plant for pets.

  • infoCharacteristics

    • Life cycle


    • Foliage type


    • Color of leaves


    • Flower color


    • Height

      4-8 feet (1.2-2.4 meters)

    • Spread

      2-4 feet (0.6-1.2 meters)

    • Plant type


    • Hardiness zones


    • Native area

      North America


  • money-bagGeneral Benefits

    • Wildlife Habitat: Cup Plant provides a food source and habitat for various pollinators such as bees and butterflies.
    • Soil Conservation: Its deep roots help prevent soil erosion and improve soil structure.
    • Drought Resistance: The plant is well adapted to survive in drought conditions once established, reducing the need for watering.
    • Aesthetic Appeal: Cup Plant features tall, sturdy stalks with bright yellow flowers that can enhance the visual appeal of gardens and natural landscapes.
    • Support for Birds: The leaves can hold water after rain, providing a drinking source for birds and small wildlife.
    • Eco-Friendly Gardening: By planting native species like Cup Plant, gardeners can promote a healthier, more sustainable ecosystem.

  • medicalMedical Properties

    • Expectorant: The plant has been traditionally used to help expel phlegm from the respiratory tract.
    • Antipyretic: Cup plant has a history of use in reducing fever, although modern evidence to support this use is lacking.
    • Diaphoretic: It has been suggested that the plant can help to induce sweating, which may be beneficial in some therapeutic situations.
    • Anti-inflammatory: Silphium perfoliatum may have anti-inflammatory properties, making it beneficial for treating conditions associated with inflammation.
    • Wound healing: There is anecdotal evidence that suggests its potential use in promoting wound healing, possibly due to the presence of certain compounds that can aid in skin regeneration.
    • Antibacterial: Some sources claim that the plant has antibacterial effects, potentially providing a natural means for preventing or treating bacterial infections.
    References for the medical properties of Silphium perfoliatum are largely based on historical use and traditional medicine, as there is a scarcity of modern scientific studies on this specific species' medicinal effects. As such, the actual efficacy and safety of Silphium perfoliatum for these uses have not been well-established in the scientific literature.

  • windAir-purifying Qualities

    This plant is not specifically known for air purifying qualities.

  • leavesOther Uses

    • Cup Plant's leaves can be used to create molds for papermaking, providing a unique texture and pattern to the handmade paper.
    • Children can use the large leaves in nature-inspired craft projects, such as creating imprints in clay or plaster.
    • The stems of Cup Plant have been historically used as a natural drinking straw by cutting a segment between the leaf joints.
    • Because of its sturdy stem, Cup Plant can serve as a natural trellis for climbing plants in a garden.
    • The deep cup-like formations made by the leaves hold water, which can be used as an emergency drinking source for small wildlife and birds.
    • Photographers and artists may utilize Cup Plant as a subject to study the interaction of light and water in nature.
    • The tall, strong stalks of Cup Plant can be used in creating rustic floral arrangements or as a base for wreaths and other decorative items.
    • Dried stalks of the plant may be used in construction of small-scale models or for crafting, such as making homemade pens or totemic figures.
    • When dried, the seeds and dried flower heads can be used in creating natural sound instruments, like shakers or rain sticks.
    • Cup Plant's heavy roots can be used in controlling erosion along stream banks or slopes due to their soil-binding properties.

Interesting Facts

  • bedFeng Shui

    The cup plant is not used in Feng Shui practice.

  • aquariusZodiac Sign Compitability

    The cup plant is not used in astrology practice.

  • spiralPlant Symbolism

    • Connection: The unique “cup” formed by the joined opposite leaves of Silphium perfoliatum, generally known as Cup Plant, symbolizes connection and unity as it often collects water that benefits wildlife.
    • Healing: Historically used for medicinal purposes by Native Americans, the Cup Plant is often associated with healing and therapeutic properties.
    • Generosity: As the Cup Plant generously provides water to birds and insects, it represents the spirit of giving and abundance.
    • Resilience: This hardy perennial's ability to thrive in various conditions and its tendency to spread, symbolizes resilience and adaptability.
    • Support: The strong, supportive stems that hold the cup-shaped leaves reflect the notion of support and reliability in relationships and communities.

Every 1-2 weeks
2500 - 10000 Lux
Not needed
Spring to early summer
As needed
  • water dropWater

    Cup plant, or Silphium perfoliatum, is a robust plant that prefers consistent moisture but can tolerate some dryness once established. During the first growing season, water the cup plant deeply once a week, providing about 1 to 1.5 gallons of water each time to establish a strong root system. After establishment, reduce watering frequency, but ensure it gets about 1 gallon every two weeks, especially during prolonged dry spells. In particularly hot and dry climates, increase the frequency to weekly watering. Always water at the base of the plant to avoid wetting the foliage, which can lead to fungal diseases.

  • sunLight

    Cup plant thrives in full sunlight, so it is best to place it in a spot where it can receive at least six hours of direct sunlight each day. It can tolerate some light shade, but too much shade can cause the plant to grow leggy and reduce its bloom. The brightest spot in a garden, such as an open area without any tree canopy or tall structures that cast shadows, is ideal for the cup plant.

  • thermometerTemperature

    The cup plant is hardy and can withstand a range of temperatures found across its native regions. It can survive minimum winter temperatures down to -30°F and is comfortable in summer temperatures up to 90°F. The ideal temperature range for the cup plant is between 60°F and 80°F, where it can thrive and produce its characteristic blooms.

  • scissorsPruning

    Cup plant can be pruned to control its height and promote bushier growth. The best time for pruning is in late winter or early spring, before new growth begins. Pruning can be done annually, cutting back the plant by a third to half of its height. This helps to maintain a more compact growth form and can prevent the tall stems from flopping over. Additionally, deadheading spent flowers can encourage a second bloom and prevent excessive self-seeding.

  • broomCleaning

    As needed

  • bambooSoil

    Cup plant, or Silphium perfoliatum, thrives in a loamy soil mix with good drainage. A soil pH of 6.0 to 7.5 is ideal for this perennial. To create the best soil mix, combine two parts garden soil, one part compost, and one part sand or perlite.

  • plantRepotting

    Cup plant typically does not need frequent repotting as it prefers to be left undisturbed. Repotting may be required every 3-5 years if it outgrows its container or the soil becomes depleted.

  • water dropsHumidity & Misting

    Cup plant is tolerant of a range of humidity levels and thrives in average outdoor conditions. It does not require any special humidity adjustments when grown in its natural environment.

  • pinSuitable locations

    • Indoor

      Grow cup plant in a sunny spot with a large container.

    • Outdoor

      Plant in well-draining soil; full sun; space 2-3 ft apart.

    • Hardiness zone

      3-9 USDA

  • circleLife cycle

    The life of Cup Plant (Silphium perfoliatum) begins as a seed, which, after being dispersed, requires a period of stratification through cold weather to germinate in spring. Upon sprouting, the seedling establishes a deep taproot and grows into a rosette of leaves during its first year, focusing on root development rather than flowering. In subsequent years, the Cup Plant develops a tall, sturdy stem and large, opposite leaves which fuse at the base to form a 'cup' that can hold water. It typically blossoms in late summer, bearing bright yellow, daisy-like flowers that attract a variety of pollinators. After pollination, it produces achenes, which are dry, one-seeded fruits that are distributed by wind or wildlife, completing its reproductive cycle. Finally, as a perennial, the Cup Plant dies back to the ground in winter, with its root system surviving to regenerate the next spring.

  • sproutPropogation

    • Propogation time

      Spring to early summer

    • Cup plant, or Silphium perfoliatum, is most commonly propagated by seed. The ideal time for sowing these seeds is either in the fall, to allow for a natural stratification process over the winter, or in the spring, after a period of artificially stratifying the seeds in your refrigerator for approximately a month to mimic winter conditions. To propagate by seed, one should plant them about 1/4 inch deep into a well-draining soil mix. The soil should be kept moist until germination, which typically occurs within two to three weeks. Once the seedlings have reached a sufficient size, they can be transplanted into the garden. It’s worth noting that the cup plant prefers full sun to partial shade and can adapt to a wide range of soil conditions, making it a resilient choice for many gardeners.