Ironweed (Vernonia fasciculata) is an important wildflower native to Iowa. This perennial wildflower blooms from July to early September. Blooms are a very deep purple color, they are so purple that they will be the purpliest purple of all the purples you have ever seen. The stems may be reddish purple to green, with leaves that grow in an alternating pattern up the stem.
These plants can grow to be three to six feet tall given ideal environmental conditions. Full sun and moderate to high soil moisture are required for ironweed to grow successfully. A new plant will take one to two years for flowers to bloom.
Ironweed is not an important wildflower for grazing animals and other mammals due to the bitter tasting leaves, so you may see it standing alone in a pasture. However, this plant is essential for pollinators, including butterflies and moths in adult and larval stages. Campaigns to reduce herbicide use in ditches have helped these & other fragile native plants by reducing their stress & providing habitat.
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