Bronze Beauty Crocus Crocus olivieri subsp. balansae 'Zwanenburg'

☠ Toxic to humans
🐾 Toxic to pets
🌸 Blooming
🍪 Not edible
‍🌱 Easy-care
crocus 'Zwanenburg'


The 'Zwanenburg' derivative of Crocus olivieri subsp. balansae is known for its unique and eye-catching appearance that comes to life during its flowering period. This enchanting plant blooms with flowers that have a goblet-like shape, characterized by their slender and graceful form which often brings vibrancy to the early spring landscape. The petals exhibit a rich, golden-yellow hue that shines brightly against the green foliage. Each bloom is distinctively marked with deep, bronzed to purplish-brown stripes or flames that run along the outer segments of the petals, enhancing their beauty and drawing the eye. The leaves of this plant are narrow and grass-like, presenting an attractive dark to grayish-green color. They emerge from the ground with a slight curl before unfolding and elongating. Along the leaf margins, one can observe a delicate silver-white stripe that adds to the elegance of the foliage. This particular variety is cherished not only for its aesthetic appeal but also for its ability to naturalize over time, creating expanding clusters of stunning blooms. The flowers are borne on short and sturdy stems that rise just above the foliage, presenting the blooms in a way that captures the attention and admiration of onlookers. The bold chromatic contrast and the whimsical appearance of this springtime beauty make it a beloved choice for gardens and landscapes aiming to provide an early pop of color.

Plant Info
Common Problems

About this plant

  • memoNames

    • Family


    • Synonyms

      Golden Crocus, Zwanenburg Bronze Crocus, Olive's Crocus, Balansae Crocus

    • Common names

      Crocus balansae, Crocus olivieri var. balansae.

  • skullToxicity

    • To humans

      The Crocus, specifically Crocus olivieri subsp. balansae 'Zwanenburg’, is generally not considered highly toxic to humans. However, it is important to note that many crocus species contain compounds that can be harmful if ingested, such as colchicine and other alkaloids. If ingested, these compounds can cause gastrointestinal upset, including nausea, vomiting, and diarrhea. In more severe cases, ingestion can lead to symptoms such as kidney and liver damage, respiratory failure, and may even be fatal if a large enough quantity is consumed. Therefore, it is recommended to avoid eating any part of the Crocus plants.

    • To pets

      The Crocus, including Crocus olivieri subsp. balansae 'Zwanenburg', can be toxic to pets if ingested. Specifically, pets such as cats and dogs may experience gastrointestinal upset, which could include symptoms like vomiting, diarrhea, abdominal pain, and drooling. More serious cases of poisoning can lead to severe health issues such as liver and kidney damage, seizures, and even death if not treated promptly. It's critical for pet owners to ensure their pets do not have access to Crocus plants, and to seek veterinary care immediately if they suspect their pet has ingested any part of the plant.

  • infoCharacteristics

    • Life cycle


    • Foliage type


    • Color of leaves


    • Flower color


    • Height

      0 feet 4 inches (10 cm)

    • Spread

      0 feet 2 inches (5 cm)

    • Plant type


    • Hardiness zones


    • Native area



  • money-bagGeneral Benefits

    • Ornamental Value: Crocus 'Zwanenburg' has striking, vibrant flowers that add beauty and color to gardens and landscapes, especially in late winter and early spring.
    • Early Bloomer: It is one of the first plants to bloom in the year, often providing flowers when little else is in bloom.
    • Attracts Pollinators: The bright flowers attract bees and other pollinators, which are essential for the health of the ecosystem.
    • Low Maintenance: Once established, Crocus 'Zwanenburg' requires minimal care, making it a suitable choice for gardeners of all skill levels.
    • Drought Tolerance: Crocus 'Zwanenburg' has a level of drought tolerance once settled, reducing the need for frequent watering.
    • Naturalizing: It can spread and naturalize in an area, which means it can multiply and come back year after year with little intervention.
    • Adaptability: This plant can adapt to a variety of soil types, although it prefers well-drained soils.

  • 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

    • Ink Production: The vibrant colors of the Crocus olivieri, particularly the purple shades, can be used to create natural inks for art and dyeing purposes.
    • Natural Dyes: The petals can be used to dye textiles or materials, giving them a bright, natural color.
    • Perfume Industry: The flowers of the Crocus olivieri can be used for their fragrance in the making of perfumes and scented oils.
    • Aesthetic Element in Culinary Presentations: The bright and attractive petals may be used as an edible decoration on salads and desserts for visual enhancement.
    • Garden Design: Due to its ornamental beauty, it is used to add color to rock gardens, borders, and woodland gardens during springtime.
    • Saffron Substitute: While not a true source of saffron, the stigmas of the flowers might be used as a saffron imitation in cooking for color, though not for flavor.
    • Botanical Illustrations: The plant can be used as a subject for botanical artists and illustrators due to its unique structure and coloration.
    • Photography: The Crocus olivieri provides attractive subject matter for photographers, particularly macro photographers focusing on plant and flower imagery.
    • Educational Use: It can be incorporated into educational programs to teach about plant biology, reproduction, and horticulture.
    • Crafts: The dried petals can be used in crafts such as making bookmarks, cards, or potpourri.

Interesting Facts

  • bedFeng Shui

    The Crocus is not used in Feng Shui practice.

  • aquariusZodiac Sign Compitability

    The Crocus is not used in astrology practice.

  • spiralPlant Symbolism

    • Renewal: The crocus is one of the first flowers to bloom, signaling the end of winter and the beginning of spring, making it a symbol of new beginnings and rebirth.
    • Hope: Its early appearance when the weather is still cold and unforgiving brings hope for the warmer and brighter days ahead.
    • Youthfulness: Associated with its early springtime appearance, the crocus symbolizes youth and the joy of youth.
    • Glee: The flower is often linked to cheerfulness and happiness, probably due to its bright colors and how it signifies the upcoming spring joy.

Every 2 weeks
10000 - 20000 Lux
Every 3 years
Not needed
  • water dropWater

    The Golden Crocus should be watered sporadically, as it is drought-tolerant and prone to rot if overwatered. During the active growth phase in the fall and early spring, ensure the soil is moist but not soggy, watering approximately once a week with about 8 ounces of water, depending on soil conditions and climate. Reduce watering after the flowers and leaves die back, and during dormancy in the summer, watering may be reduced further or even ceased if rainfall provides sufficient moisture.

  • sunLight

    The Golden Crocus thrives in full sun to partial shade. It's best planted in a spot that receives direct morning sunlight and some afternoon shade, or dappled sunlight throughout the day. Avoid planting in full shade, as this can inhibit blooming.

  • thermometerTemperature

    The Golden Crocus prefers cool to moderate temperatures with a growing season range between 35 to 65 degrees Fahrenheit. It can survive winter cold down to about 15 degrees Fahrenheit but should not be exposed to prolonged periods of extreme cold. The ideal temperature for this crocus is around 50 to 60 degrees Fahrenheit during its active growing season.

  • scissorsPruning

    Pruning the Golden Crocus is generally not necessary as it is a low-maintenance plant. However, after the flowers fade, you can deadhead spent blooms to maintain a tidy appearance. At the end of the flowering season, allow the leaves to die back naturally without cutting them off, as they provide nourishment for the next year's growth.

  • broomCleaning

    Not needed

  • bambooSoil

    The Orange Crocus requires well-draining soil with a pH of 6.0 to 8.0. A mixture containing equal parts of potting soil, coarse sand, and peat or compost is ideal. Ensure the pot has adequate drainage to prevent standing water.

  • plantRepotting

    The Orange Crocus should be repotted every 3 to 4 years or when the corms become crowded. It is best done when the plant is dormant, typically in late summer before the growth season begins.

  • water dropsHumidity & Misting

    The Orange Crocus thrives in average room humidity levels. It does not require high humidity, making it well-suited for typical home environments.

  • pinSuitable locations

    • Indoor

      Place in bright, indirect light and cool temperatures.

    • Outdoor

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

    • Hardiness zone

      3-8 USDA

  • circleLife cycle

    Crocus olivieri subsp. balansae 'Zwanenburg', commonly known as 'Zwanenburg Bronze Crocus', starts its life cycle as a corm, a storage organ that survives through the dormancy period. In early spring or late winter, leaf growth emerges, followed by the flowering stage where vibrant, cup-shaped blooms appear. After flowering, the plant undergoes pollination, potentially with the assistance of early-season insects. Following successful pollination, seed development occurs, and once mature, the seeds are dispersed into the surrounding soil. The foliage begins to die back as the plant goes into a period of dormancy through the hotter summer months. The corms will remain dormant underground until the conditions are suitable again for the next growth cycle, with each corm capable of producing offsets to increase the plant population.

  • sproutPropogation

    • Propogation time


    • The most popular method of propagation for Crocus olivieri subsp. balansae 'Zwanenburg', commonly referred to as Zwanenburg Bronze Crocus, is by dividing corms. The best time to carry out this process is in the summer after the foliage has died back and the corms have entered a period of dormancy. To propagate, carefully dig up the mature corms and gently separate the smaller cormels—the offset bulbs—from the base of the parent corm. These cormels can be replanted immediately, about 3 inches (approximately 7.5 cm) deep and spaced 3 to 4 inches (about 7.5 to 10 cm) apart in well-draining soil and in an area with full to partial sunlight. By the next spring, these cormels will have established themselves and should bloom.