Giant Ironweed Pollen Color, Bloom Season and Bee Forage

Visual guideGiant Ironweed pollen

Photo: Greg Hume · CC BY-SA 4.0

Plant Facts

SeasonSummer to Fall

USDA Zone5 - 9

Plant TypeWildflower

ForagePollen and nectar

Pollen ValueMedium

Nectar ValueMedium

Color FamilyWhite and cream

Scientific NameVernonia gigantea

Common NamesGiant ironweed, Tall ironweed

Native RegionsEastern and central United States, Southern Ontario

Range StatusNative to eastern and central North America.

Color ConfidenceModerate

Color MethodAn Ohio State University Extension Master Gardener account reports white pollen collected from ironweed; the off-white swatch is approximate.

Reviewed2026-10-11

Quick Answer

Giant Ironweed pollen is shown in this guide as a white and cream tone. It is listed as wildflower, associated with summer to fall bloom timing, USDA zone 5 - 9, and pollen and nectar forage value.

Pollen Color Notes

The visual color shown for Giant Ironweed is grouped broadly with white and cream pollen tones. It is intended for comparison and identification support, not as a laboratory measurement.

Pollen color is highly variable. Lighting, pollen age, moisture, collection method, cultivar, and local growing conditions can all change how pollen appears. Use this as general visual guidance, not a scientific color standard or guaranteed field match.

Bloom, Zone, and Forage Context

Giant Ironweed is listed for summer to fall. The record lists USDA zone 5 - 9; hardiness zones are planning context, not a precise flowering calendar. Approximate bloom months in the supplemental notes: July, August, September.

Its forage type is pollen and nectar, with pollen value marked as medium and nectar value marked as medium. Ironweed provides late-summer pollen and nectar and supports both generalist pollinators and specialist long-horned bees.