Ornamental Onion Allium 'Crans'

👤 Non-toxic to humans
🐾 Toxic to pets
🌸 Blooming
🍪 Edible
‍🌱 Easy-care
allium 'Crans'


The Allium 'Crans' is characterized by its distinctive and ornamental ball-shaped flower clusters that bloom in stunning shades of purple, magenta, or violet. These showy globes are made up of many small, star-shaped flowers tightly packed together, creating a dramatic visual impact. The flowers are perched atop slender stems that rise above the plant's foliage, lending an airy grace to the overall look of the plant. The foliage itself consists of slender, green leaves that are typically strap-shaped, forming a tuft or clump at the base of the plant. These leaves may have a slight onion-like scent when crushed or bruised, reflecting their family characteristics. The Allium 'Crans' lends itself well to providing a pop of color and texture to gardens and landscape designs.

Plant Info
Common Problems

About this plant

  • memoNames

    • Family


    • Synonyms

      Ornamental Onion, Flowering Onion, Crans Allium

    • Common names

      Allium 'Crans'.

  • skullToxicity

    • To humans

      Allium 'Crans' is not a commonly recognized name for an Allium species, but assuming it is closely related to other Alliums, such as onions, garlic, chives, and leeks, these plants are generally not highly toxic to humans. However, some people may have a sensitivity or allergy to Allium species. In large amounts or with prolonged exposure, they can cause gastrointestinal irritation, nausea, vomiting, or diarrhea. For those with an allergy, symptoms could include hives, skin irritation, or difficulty breathing.

    • To pets

      Alliums, including plants closely related to onions, garlic, chives, and leeks, are considered toxic to pets, especially cats and dogs. Symptoms of Allium toxicity in pets can begin with gastrointestinal upset, such as vomiting and diarrhea. More severe cases can lead to lethargy, abdominal pain, and signs of anemia, like pale gums, rapid heart rate, or weakness. Ingesting a large amount or chronic exposure to Allium species can cause oxidative damage to red blood cells, leading to potentially life-threatening hemolytic anemia. It is strongly advised to prevent pets from ingesting any part of these plants.

  • infoCharacteristics

    • Life cycle


    • Foliage type


    • Color of leaves


    • Flower color


    • Height

      1-2 feet (0.3-0.6 meters)

    • Spread

      0.5-1 feet (0.15-0.3 meters)

    • Plant type


    • Hardiness zones


    • Native area



  • money-bagGeneral Benefits

    • Attractive to pollinators: Allium 'Crans', commonly known as ornamental onion, provides nectar for bees and other beneficial insects, aiding in the pollination of nearby plants.
    • Low maintenance: Ornamental onions require minimal care once established, making them suitable for gardeners of all levels.
    • Drought-tolerant: These plants are quite resilient in dry conditions, reducing the need for frequent watering.
    • Pest-resistant: Ornamental onions are generally resistant to pests, helping to protect the surrounding garden without the need for chemical interventions.
    • Deer and rodent-repellent: The pungent smell deters deer and rodents, which might otherwise damage gardens and landscapes.
    • Adds height and structure: With their tall stems and spherical blooms, ornamental onions add vertical interest to gardens and landscaping projects.
    • Long blooming season: These plants have a lengthy flowering period which provides visual appeal in the garden for an extended time.
    • Easy to propagate: Ornamental onions can be easily propagated by division, allowing gardeners to spread them throughout the landscape or share with others.
    • Versatile design element: Their unique shape and form make them a versatile design element in both traditional and contemporary garden designs.
    • Culinary use: While not the primary reason for cultivation, some ornamental onions can also be used in the kitchen for their flavorful bulbs and edible flowers.

  • 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

    • Allium 'Crans', more commonly referred to as ornamental onion, can be used as a natural pest deterrent in gardens, as its strong scent can repel certain insects and animals.
    • Ornamental onions can serve as a companion plant for various vegetable crops, helping to mask their scent and prevent pests.
    • These plants can be used as cut flowers for decorative purposes, adding an interesting and unique aesthetic to flower arrangements.
    • Dried seed heads of the Crans can also be used in crafts or as part of dried flower arrangements for their striking spherical shapes.
    • The sturdy stems of ornamental onions can be incorporated into garden sculptures or used as natural stakes for supporting other plants.
    • They can act as a natural color dye for fabrics, as some Allium species produce pigments that can be used to dye cloth.
    • Allium 'Crans' can be used in educational settings, such as school gardens, to teach students about bulb growth and ornamental plant cultivation.
    • These plants can serve as a food source for pollinators, providing nectar for bees, butterflies, and other beneficial insects when other food sources are scarce.
    • Ornamental onions, with their distinctive appearance, can be used for artistic inspiration in photography, painting, and other visual arts.
    • The reflective quality of their spherical seed heads can be utilized in landscape design to create visual interest with sunlight and shadow play.

Interesting Facts

  • bedFeng Shui

    Allium 'Crans' is not used in Feng Shui practice.

  • aquariusZodiac Sign Compitability

    Allium 'Crans' is not used in astrology practice.

  • spiralPlant Symbolism

    • Strength and Courage: Alliums, commonly known as ornamental onions, often symbolize strength and courage due to their robust and sturdy stems that stand tall and resist strong winds.
    • Unity and Patience: The tightly clustered blossoms of the allium represent unity, signifying how many individual elements can come together to create a strong and harmonious whole. Additionally, alliums have a slow growth process, which can be seen as a symbol of patience.
    • Good Fortune and Prosperity: In some cultures, alliums are thought to bring luck and wealth, making them a favored plant in gardens and as a cut flower for celebrations.
    • Protection: The pungent smell of allium plants, which includes garlic and onions, is believed to offer protection by repelling evil spirits and negativity.

Every week
2500 - 10000 Lux
Every year
Spring-Early Summer
Not needed
  • water dropWater

    Ornamental onions, like Allium 'Crans', prefer to be watered thoroughly, ensuring that the soil is evenly moist but not waterlogged. Water them once a week with about 1 gallon of water per plant, depending on the weather conditions; less if it's rainy or cool, more if it's particularly hot and dry. During the active growing season in spring and early summer, keep the watering consistent, but once the foliage begins to die back, you can reduce watering as the plant enters dormancy. Always check the top inch of soil for dryness before watering again.

  • sunLight

    Ornamental onions thrive best in full sun conditions, which means they should receive at least 6 to 8 hours of direct sunlight daily. The ideal spot for Allium 'Crans' is an area where it can bathe in unobstructed sunlight throughout the day, promoting strong and healthy growth. Avoid heavily shaded areas, as insufficient light may lead to weak stems and poor flowering.

  • thermometerTemperature

    Ornamental onions are hardy and can tolerate a wide range of temperatures. Allium 'Crans' grows best in temperatures between 55°F and 75°F but can survive minimum temperatures down to -4°F. For optimal growth, place the plant in a location where it is protected from extreme heat, as prolonged exposure above 86°F can be detrimental.

  • scissorsPruning

    Ornamental onions like Allium 'Crans' should be pruned to remove spent flower stalks and encourage a tidy appearance. Pruning can be done after flowering, usually in late summer or early fall. Cut the flower stems down to the base of the plant, and remove any yellowing or dead foliage. Annual pruning helps prevent self-seeding and keeps the plant looking its best.

  • broomCleaning

    As needed

  • bambooSoil

    Ornamental onion 'Crans' thrives in well-draining soil with a mix of loam, sharp sand, and compost to ensure good drainage and fertility. The best soil pH for this plant is between 6.0 and 7.0, slightly acidic to neutral.

  • plantRepotting

    Ornamental onions generally do not need frequent repotting; repot 'Crans' only if it outgrows its container or every 3 to 4 years to refresh the soil.

  • water dropsHumidity & Misting

    The ornamental onion 'Crans' is tolerant of a wide range of humidity levels and does not have specific humidity requirements.

  • pinSuitable locations

    • Indoor

      Ensure bright light and well-draining soil for indoor 'Crans'.

    • Outdoor

      Plant in sunny spot with good drainage; tolerates cold.

    • Hardiness zone

      4-8 USDA

  • circleLife cycle

    Allium 'Crans', commonly known as ornamental onion, begins its life cycle when a gardener plants its bulb in well-draining soil, usually in the fall. The bulb remains dormant over the winter, with the cold period providing vernalization necessary for spring growth. In spring, the bulb sprouts and the plant develops a sturdy stem and strappy green leaves, followed by spherical clusters of star-shaped flowers that can be purple, pink, or white, depending on the variety. After flowering, which occurs in late spring to early summer, the plant sets seed, which can be dispersed by wind or collected for propagation. Once the flowering and seed-setting stages are complete, the foliage begins to die back and the plant enters a period of dormancy during the hot summer months. In the next growth cycle, the bulb can either be left in the ground to regenerate for the following season or lifted and divided to propagate new plants.

  • sproutPropogation

    • Propogation time

      Spring-Early Summer

    • Allium 'Crans', commonly known as ornamental onion, is most popularly propagated through division. This method is ideally undertaken in either spring or fall. To propagate by division, one should carefully lift the clump of the plant from the ground and gently separate the bulbs with their hands or a knife if necessary, ensuring that each division has at least one piece of the original bulb attached with roots. These separated bulbs can be immediately replanted in well-drained soil at a depth thrice their diameter (for example, a 2-inch bulb should be planted 6 inches deep, which is approximately 5 cm planted 15 cm deep), and spaced approximately 8 to 12 inches apart (20 to 30 cm). Water the newly planted bulbs moderately to help establish them. This straightforward process helps maintain the vigor of the plant and enables gardeners to share or spread their Allium 'Crans' to other parts of the garden with relative ease.