Black Knapweed Centaurea 'Jordy'

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


Centaurea 'Jordy', commonly known as the Black Knapweed, is a distinctive ornamental plant known for its deep burgundy flowers. These flowers are notable for their fluffy thistle-like appearance and are often contrasted with silver or gray-green foliage that forms a basal clump. The flower heads are composite, meaning that each head is actually made up of many tiny flowers bundled together, giving an overall tufted look that is attractive to pollinators such as bees and butterflies. The petals have a fringed, feathery effect, which enhances the texture of the bloom. The foliage of Black Knapweed is lance-shaped, with a slightly hairy texture that adds to the soft, downy feel of the plant. The silver to gray-green hue of the leaves serves as an excellent backdrop for the deeply colored flowers, making them stand out even more strikingly. The overall impression of Black Knapweed is one of bold color and interesting textures, creating an eye-catching display in any garden setting where it is planted.

Plant Info
Common Problems

About this plant

  • memoNames

    • Family


    • Synonyms

      Black Knapweed, Hardheads, Knapweed, Jordy.

    • Common names

      Centaurea 'Jordy'

  • skullToxicity

    • To humans

      The Centaurea 'Jordy', commonly known as the Black Knapweed or Bachelor's Button, generally does not contain high levels of toxic substances that are harmful to humans. In most cases, it is not considered poisonous to people and does not cause serious symptoms upon ingestion. However, as with any non-food plant, sensitivity or allergic reactions could occur in some individuals if parts of the plant were ingested. It is always advisable to exercise caution and avoid eating plants not known to be safe for human consumption.

    • To pets

      The Centaurea 'Jordy', commonly referred to as the Black Knapweed or Bachelor's Button, is not typically listed as a toxic plant to pets such as dogs and cats. It does not contain significant levels of compounds known to be harmful to pets, so poisoning is not a common concern. However, individual animals may have different sensitivities, and ingestion of non-food plants can sometimes lead to gastrointestinal upset or allergic reactions. If a pet ingests this plant and shows symptoms of distress, it is best to consult with a veterinarian.

  • infoCharacteristics

    • Life cycle


    • Foliage type


    • Color of leaves


    • Flower color


    • Height

      2-3 feet (60-90 cm)

    • Spread

      1-2 feet (30-60 cm)

    • Plant type


    • Hardiness zones


    • Native area



  • money-bagGeneral Benefits

    • Attracts Pollinators: Centaurea 'Jordy', commonly known as Cornflower 'Jordy', is attractive to bees and butterflies, enhancing pollination in gardens.
    • Drought Tolerant: Once established, Cornflower 'Jordy' has good drought resistance, reducing the need for frequent watering.
    • Low Maintenance: It requires minimal maintenance, making it suitable for gardeners of all levels.
    • Aesthetic Appeal: With its deep burgundy flowers, it adds striking color and visual interest to landscapes and gardens.
    • Deer Resistant: This plant is not a preferred food source for deer, helping to prevent damage in areas where deer are common.
    • Long Blooming: Cornflower 'Jordy' offers a lengthy blooming period, providing color in the garden throughout the growing season.
    • Soil Adaptable: It can thrive in a variety of soil types, making it a versatile choice for different garden conditions.
    • Edging and Borders: The plant's size and form make it suitable for use in edging and border planting, giving structure to garden designs.

  • 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

    • Centaurea 'Jordy', commonly known as Bachelor's Button, can be used as a natural fabric dye, offering hues ranging from grey to lavender depending on the mordant used.
    • The petals of Bachelor's Button can be used to add color to salads, as an edible decoration, or as an ingredient in floral butters and spreads.
    • Dried Bachelor's Button flowers can be incorporated into potpourri mixtures to add color and a mild, clove-like fragrance.
    • The plant can serve as an indicator for soil fertility; Bachelor's Button tends to thrive in soils that have a medium to high level of nutrients.
    • Bachelor's Button can be used in flower arrangements and crafts due to its vivid color and its ability to retain its shape and color when dried.
    • The extract from the petals is sometimes used in the cosmetic industry as a natural coloring agent in makeup products such as rouge or lipstick.
    • As a companion plant in the garden, Bachelor's Button can attract beneficial insects such as ladybugs and lacewings, which prey on garden pests.
    • The flowers can be used to infuse syrups or spirits, giving a unique flavor to cocktails or non-alcoholic beverages.
    • Bachelor's Button can be used in educational settings, such as schools or nature programs, to demonstrate the process of pollination and the importance of pollinators.
    • The vibrant flowers can be pressed and used in the art of botanical illustration or to create handmade greeting cards or bookmarks.

Interesting Facts

  • bedFeng Shui

    The Bachelor's Button is not used in Feng Shui practice.

  • aquariusZodiac Sign Compitability

    The Bachelor's Button is not used in astrology practice.

  • spiralPlant Symbolism

    • Love and Devotion: Centaurea 'Jordy', commonly known as Bachelor's Button or Cornflower, often represents love and devotion in the language of flowers. Its rich, deep colors suggest the intensity of feeling and a strong commitment to a loved one.
    • Felicity and Delicateness: The delicate nature of the flower symbolizes joy and gentleness. It's often used to convey a message of happiness in a soft and subtle way.
    • Hope and Positivity: The bright colors of Bachelor's Button are also seen as symbols of hope and positive thoughts. They are given to lift spirits and encourage a positive outlook.
    • Remembrance: This plant is often associated with remembrance, particularly in some cultures that use it as a symbol to honor deceased loved ones during certain commemorations, like Memorial Day.

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

    The Black Knapweed or Centaurea 'Jordy' requires moderate watering. It is essential not to overwater, as this plant prefers well-drained soil. Generally, you should water Black Knapweed once a week with about 1 gallon of water, but this could vary depending on climate conditions. During the growing season in spring and summer, check the soil moisture regularly and water when the top inch of the soil feels dry. In cooler months, reduce the watering frequency to prevent waterlogging.

  • sunLight

    The Black Knapweed thrives in full sun exposure. It should be positioned in a spot where it can receive at least six to eight hours of direct sunlight daily. This plant's best spot is an area where it can enjoy the morning sun, which is less intense than the afternoon sun, but it is quite adaptable and can also tolerate the heat of the later day sun provided it's well-watered.

  • thermometerTemperature

    The Black Knapweed prefers a temperate climate and can tolerate a range of temperatures. Ideally, it grows best when temperatures are between 60 to 75 degrees Fahrenheit. It can survive temporarily in temperatures as low as 20 degrees Fahrenheit and as high as 85 degrees Fahrenheit, though extreme temperatures should be avoided to prevent stress on the plant.

  • scissorsPruning

    Pruning Black Knapweed involves deadheading spent flowers to encourage new blooms and maintain the plant's appearance. Prune in the late winter or early spring before new growth begins, as this helps to shape the plant and remove any dead or damaged stems. Cutting back the plant by about one-third every year helps to keep it vigorous and promotes a bushy growth habit.

  • broomCleaning

    Not needed

  • bambooSoil

    The Centaurea 'Jordy', commonly known as Black Knapweed, thrives best in well-draining soil with a mix of loam, sand, and compost, providing a balance of moisture retention and drainage. A slightly acidic to neutral pH, between 6.0 and 7.0, is ideal for this plant.

  • plantRepotting

    Black Knapweed does not need frequent repotting and can be repotted every two to three years, or when it has outgrown its current container, to ensure it has sufficient space to grow.

  • water dropsHumidity & Misting

    Black Knapweed is quite adaptable but prefers moderate humidity levels. This plant can tolerate some variation in humidity, but extreme conditions should be avoided.

  • pinSuitable locations

    • Indoor

      Provide bright light, well-draining soil, and moderate water.

    • Outdoor

      Plant in full sun to part shade, in well-draining soil.

    • Hardiness zone

      3-8 USDA

  • circleLife cycle

    The Centaurea 'Jordy', commonly known as Bachelor's Button or Knapweed, starts its life cycle from seed, which germinates in soil rich in organic matter with full sun to partial shade exposure. Seedlings emerge, displaying their first true leaves, and initiate the vegetative growth stage, developing a robust root system and foliage. As the plant matures, it enters the budding stage where flower buds form, leading to the flowering stage, characterized by the blooming of its distinct, deep burgundy, almost black flowers that attract pollinators. After pollination, the plant sets seeds, marking the reproductive stage. These seeds will eventually disperse, either by wind, water, or activity of animals and begin a new life cycle. In cold climates, Centaurea 'Jordy' may die back in winter, only to resume growth in spring if it is a perennial variety, or might need replanting if it is grown as an annual.

  • sproutPropogation

    • Propogation time

      Spring-Early Summer

    • Propogation: The most popular method of propagation for the Centaurea 'Jordy', commonly known as the Black Knapweed 'Jordy', is through seed sowing. The best time to sow the seeds is in the spring after the danger of frost has passed, or indoors in trays a few weeks before the last expected frost. To propagate, sprinkle the seeds lightly on well-drained soil and cover with a very thin layer of soil or vermiculite. Ideally, the soil should be kept moist until germination, which usually occurs within 2 to 3 weeks. Seedlings can be transplanted outdoors once they are large enough to handle and after being gradually acclimatized to outdoor conditions. This process is known as 'hardening off' and ensures young plants are not shocked by the sudden change in environment.