Bachelor's button Centaurea 'Amethyst on Ice'

👤 Non-toxic to humans
🐾 Non-toxic to pets
🌸 Blooming
🍪 Not edible
‍🌱 Easy-care
knapweed 'Amethyst on Ice'


The Centaurea 'Amethyst on Ice', commonly known as the Bachelor's button or cornflower, is a striking perennial plant that boasts a unique and captivating appearance. It features bushy grey-green foliage that provides a soft, textured backdrop for its showy flowers. The blooms are a standout feature, with a delicate yet vibrant array of florets that possess a lavender to amethyst hue, giving the impression of a frosty shimmer or ice-coated petals. These florets are long-lasting and are surrounded by a ruff of lacy, fringed bracts that enhance the ornamental appeal. The flower heads themselves are quite enchanting and create a dazzling display against the contrasting foliage. With its plush flowers radiating cool tones, the Bachelor's button 'Amethyst on Ice' adds a touch of frosty elegance to any garden setting.

Plant Info
Common Problems

About this plant

  • memoNames

    • Family


    • Synonyms

      Amethyst In Snow Mountain Bluet, Perennial Cornflower, Bachelor's Button, Mountain Bluet

    • Common names

      Centaurea 'Amethyst on Ice'.

  • skullToxicity

    • To humans

      Amethyst in Snow is not commonly listed as a poisonous plant to humans. As with any plant, sensitive individuals may experience mild irritation or an allergic reaction upon handling or ingesting it, but it is generally considered safe. If a person were to ingest part of the plant and experience symptoms like stomach pain, vomiting, or diarrhea, they should consult a medical professional. It's always prudent to err on the side of caution and avoid ingesting parts of ornamental plants.

    • To pets

      Amethyst in Snow, like its human toxicity profile, is not typically known to be toxic to pets. However, ingestion can potentially cause mild gastrointestinal irritation in some animals. If a pet ingests this plant and shows signs of distress such as vomiting, diarrhea, or unusual lethargy, it is advisable to contact a veterinarian. It is best to keep an eye on pets around any plants, as individual reactions can vary.

  • infoCharacteristics

    • Life cycle


    • Foliage type


    • Color of leaves


    • Flower color


    • Height

      1-2 feet (30-60 cm)

    • Spread

      1-2 feet (30-60 cm)

    • Plant type


    • Hardiness zones


    • Native area



  • money-bagGeneral Benefits

    • Aesthetic Appeal: The Centaurea, commonly known as Bachelor's Button, has strikingly beautiful amethyst-colored flowers that add visual interest to any garden or landscape.
    • Ease of Growing: Bachelor's Button is known for being easy to grow and maintain, making it a great choice for gardeners of all skill levels.
    • Drought Tolerance: This plant is quite drought-tolerant once established, reducing the need for frequent watering and making it suitable for xeriscaping.
    • Pollinator-Friendly: The vibrant flowers of the Bachelor's Button attract bees, butterflies, and other beneficial pollinators, supporting biodiversity.
    • Deer Resistance: Bachelor's Button is generally resistant to deer, which is especially beneficial in areas where deer browsing can be a problem for gardeners.
    • Long Blooming Period: This plant has a long flowering season, providing color and interest in the garden for an extended period.
    • Cutting Flower: Its flowers are excellent for cutting and using in fresh floral arrangements, adding beauty both in the garden and indoors.

  • medicalMedical Properties

    This plant is not used for medical purposes.

  • windAir-purifying Qualities

    This plant is not specifically known for air purifying qualities.

  • leavesOther Uses

    • Crafting dried flower arrangements: The dried flowers of Centaurea 'Amethyst on Ice' can maintain their shape and color, making them a perfect choice for creating everlasting floral displays.
    • Photography prop: The stunning purple flowers can be used as a natural prop in photography, especially in garden and macro photography.
    • Educational tool: Botany students and enthusiasts can study the Centaurea 'Amethyst on Ice' for understanding plant morphology and the specifics of the Asteraceae family.
    • Artistic inspiration: Artists may use the flower as a subject for painting, sketching, or even as a muse for color themes and patterns in various art projects.
    • Fabric dyeing: Historically, plants from the Centaurea genus have been used for dyeing fabric, and Amethyst on Ice could potentially be used to create a unique purple dye.
    • Fragrance extraction: If the variety has a notable scent, it could be used in the making of perfumes or potpourris.
    • Garden companion planting: This plant can be used to attract beneficial insects to the garden, promoting a healthier ecosystem around vegetable crops or ornamental beds.
    • Theme gardens: Centaurea 'Amethyst on Ice' would suit well in a monochromatic purple garden theme or a 'cool colors' garden alongside blues and greens.
    • Natural confetti: The petals could be used as a biodegradable confetti option for celebrations, particularly fitting in with a purple color scheme.
    • Culinary decoration: While typically not eaten, the petals might be used to decorate dishes for a pop of color, assuming no pesticides have been used on the plants.

Interesting Facts

  • bedFeng Shui

    The plant Amethyst in Snow is not used in Feng Shui practice.

  • aquariusZodiac Sign Compitability

    The plant Amethyst in Snow is not used in astrology practice.

  • spiralPlant Symbolism

    • Uniqueness: The striking appearance of Amethyst in Snow, with its crisp white petals and contrasting purple center, symbolizes the notion of standing out and being unique in a crowd.
    • Introspection: The "amethyst" in its name can be associated with the crystal known for its meditative qualities, representing looking inward and personal growth.
    • Refinement: Often, bachelor buttons' neat form and delicate petals are connected with elegance and high standards, evoking a sense of sophistication.
    • Love and Devotion: In floral language, bachelor buttons are traditionally tied to love and the commitment one person holds for another, as they were once worn by young men in love.
    • Hope: The bright and resilient nature of the flower suggests hope and optimism for the future.

Every 1-2 weeks
2500 - 10000 Lux
Every 2-3 years
Spring-Early Summer
As needed
  • water dropWater

    The Mountain Bluet, also known as Centaurea 'Amethyst on Ice', requires moderate watering to thrive. It should be watered deeply when the top inch of soil feels dry, which might be approximately once a week depending on the climate and soil conditions. It's crucial to avoid overwatering, as this plant is sensitive to soggy soil which can lead to root rot. A good practice is to provide the plant with about 1 gallon of water during each watering session, ensuring the soil is moist but not waterlogged. During hot and dry periods, increase the frequency of watering, and reduce it during colder, wetter months.

  • sunLight

    Mountain Bluet prefers full sun to partial shade. The best spot for this plant is in an area where it can receive at least 6 hours of direct sunlight. However, if you are in an area with very hot summers, providing some afternoon shade will help protect the plant from scorching. Avoid deep shade as it may result in poor blooming and leggy growth.

  • thermometerTemperature

    Mountain Bluet thrives in temperate conditions and can tolerate a range of temperatures. The plant can survive minimum temperatures down to about 0 degrees Fahrenheit, making it suitable for colder climates. The ideal temperature range for healthy growth is typically between 60 to 75 degrees Fahrenheit. It's important to protect it from extreme heat or cold, as temperatures above 85 degrees or below freezing can stress the plant.

  • scissorsPruning

    Pruning Mountain Bluet helps to encourage bushier growth and promote more vigorous flowering. It's best to prune the plant in early spring or after it has finished blooming. Pruning can be done by cutting back the spent flowers and about a third of the plant's height to stimulate new growth and second bloom. Often, a light prune once or twice a year is enough to maintain its shape and health.

  • broomCleaning

    As needed

  • bambooSoil

    The best soil mix for Cornflower 'Amethyst on Ice' is a well-draining, fertile loam with a pH of around 6.0 to 7.0. Incorporating compost or aged manure into the soil will enrich it and maintain the right nutrient balance for this plant.

  • plantRepotting

    Cornflower 'Amethyst on Ice' is typically grown as an annual and therefore does not usually require repotting. If grown as a perennial, it should be repotted or divided every 2 to 3 years to rejuvenate its growth.

  • water dropsHumidity & Misting

    Cornflower 'Amethyst on Ice' is tolerant of a wide range of humidity levels but prefers a moderate condition. Normal outdoor humidity is generally suitable for this plant, so special humidity adjustments are not necessary.

  • pinSuitable locations

    • Indoor

      Ensure full sun, well-drained soil, and moderate watering for Cornflower.

    • Outdoor

      Plant in full sun, well-draining soil, and water regularly.

    • Hardiness zone

      3-9 USDA

  • circleLife cycle

    Centaurea 'Amethyst on Ice', commonly known as Amethyst Cornflower or Mountain Bluet, begins its life cycle with seed germination, which occurs in warm soil temperatures after the last frost of spring. The emerging seedlings develop into rosettes of foliage, which over several weeks grow into bushy plants with silver-green leaves. As the plant matures, it enters the flowering stage in late spring or early summer, producing showy, thistle-like flowers with fringed, purple petals and a creamy white center. After pollination, often by bees and butterflies, the flowers produce seeds that mature and are eventually dispersed to begin a new generation. Throughout the growing season, the plant may experience vegetative growth and repeated blooming phases, especially if deadheaded to encourage additional flowers. The plant’s life cycle may conclude at the end of the growing season if it is an annual, but if it is perennial, it will enter dormancy in winter, only to begin the cycle again the following spring.

  • sproutPropogation

    • Propogation time

      Spring-Early Summer

    • The most popular method of propagation for the Centaurea 'Amethyst on Ice', also known as Mountain Bluet or Perennial Cornflower, is by division. This is best done in the early spring or fall when the plant is not in active bloom. To propagate by division, carefully dig up the entire plant, ensuring you maintain a good portion of the root system. Once excavated, gently separate the plant into smaller sections, each with a portion of the root system intact. These sections can then be replanted in well-draining soil at the same depth they were originally growing. It is important to water the new divisions thoroughly after planting to help establish them. This method allows the gardener to quickly and effectively increase their stock of Centaurea 'Amethyst on Ice'.