Giant ironweed - Vernonia gigantea (Taxonomy, Characteristics, Flower, Images)

Giant ironweed

Also known as: Ironweed

Giant ironweed (Vernonia gigantea) is a plant species in the Asteraceae family and related to the sunflower. This species grows in countrysides and fields. Giant ironweed has flowers shaped like miniature pipes.

Scientific classification

Species

Giant ironweed (Vernonia gigantea)

Asters bellflowers fanflowers and allies

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Weeds

Weed or not

Perennial

Lifespan

Herb

Plant Type

Summer, Fall

Bloom Time

Fall

Harvest Time

91 cm to 2 m

Plant Height

90 cm to 1.8 m

Spread

Green

Leaf Color

2.5 cm

Flower Size

Brown, Copper, Silver, Gray

Fruit Color

Purple, Pink

Flower Color

Green, Purple, Lavender

Stem Color

Images of Giant ironweed

Distribution of Giant ironweed

Distribution Map

Giant ironweed is a plant native to eastern regions of North America. It has been introduced and now persists in the wild in parts of Europe and Asia. This species adapts well outside its native range, often found naturalized in these non-native environments.

Native

Cultivated

Invasive

Introduced

No species reported

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Habitat

Roadsides, meadows, open woodlands

Hemisphere Trend Curve

Northern

Sorthern

Flowering

Fruiting

Culture

Garden Use

Giant ironweed is a popular perennial grass prized for its green foliage and bright purple clusters of flowers. It is used as an ornamental plant and is essential in bee, hummingbird, and butterfly gardens. Plant it with bear claw, frostweed, seaside goldenrod, coontie, native plumbago, red salvia, dicliptera, and Florida pellitory for contrasting color and a constant supply of nectar.

Symbolism

Emotions, ideas and actions

Name Story

Giant ironweed: The common name is based on its tough stem. Its purple flowers are quite attractive despite having "weed" in its name. As the plant is bigger than typical Vernonia plants, it is called giant ironweed.

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Toxicity

Giant ironweed contains toxins in its roots, stem, and leaves. Contact with the plant's sap can irritate skin causing redness, itching, and inflammation. It can also irritate the eyes and mouth, leading to redness, watery eyes, blurry vision, and blisters or sores in and around the mouth.

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Quickly Identify Giant ironweed

Tall erect stature reaching 3-12 feet (0.9-3.7 m), giving a stately presence.

Distinctive flat-headed panicle of flowers, 16 inches (41 cm) wide, in shades of lavender, magenta, or deep purple.

Leaves ranging from ovate to elliptical, up to 9 inches (23 cm) long, featuring serrated edges.

Gray to brown achenes with short and long bristly hairs aiding wind-driven dispersal.

Stem varying from light green to purplish green, unbranched or sparsely branched, providing sturdy support.

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Care Guide for Giant ironweed

Every week

Water

Full sun

Sunlight

5 - 35 ℃

Ideal Temperature

Garden Soil

Soil Type

Water: Giant ironweed prefers moist habitats and consistent watering (weekly) but is drought-tolerant once established. It thrives outdoors, benefiting from natural rainfall, and is suitable for rain gardens due to its robust nature and ability to adapt to varying moisture levels.

Fertilize: For giant ironweed, use balanced, slow-release fertilizers in spring and mid-summer at half the standard rate for best growth and flowering. Monthly applications during establishment help root development, reducing as giant ironweed matures. Adjust fertilization in fall to prepare for dormancy and avoid over-application to prevent runoff.

Pruning: Giant ironweed flourishes with regular pruning in early to late spring, enhancing growth and bloom production. Remove dead stems and trim one-third of last year's growth to maintain shape and airflow. Effective pruning improves giant ironweed's appearance and vigor for a striking display.

Propagation: Giant ironweed propagates mainly through sowing, with spring being the ideal season. It has moderate difficulty in propagation, characterized by the emergence of new leaves and shoots. Maintaining adequate moisture is crucial during the germination phase.

Repotting: Giant ironweed grows best when repotted every 2-3 years in spring. Use a large, deep pot and water thoroughly post-repotting. Position in full sun to partial shade, ensuring moist soil without waterlogging for optimal health.

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Images of Giant ironweed

Distribution of Giant ironweed

Culture

Toxicity

Quickly Identify Giant ironweed

Care Guide for Giant ironweed

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