Enjoying the Ironweed (Vernonia gigantea)

This time of year you will probably notice in the fields a beautiful tall purple flowering plant dominating the scene. It’s likely that it is mixed with some beautiful golden rod (solidago) creating a wonderful purple and gold landscape. That tall purple flower is a native plant called ironweed. There are several different varieties of ironweed and all of them are great native plants for pollinators to enjoy. Of course, we can too!

Giant Ironweed or Vernonia gigantea

Th variety of ironweed that I see the most is giant ironweed or Vernonia gigantea. I even have one in our front garden that planted itself a few years ago much to my wife’s dismay. It’s not that she doesn’t like ironweed, it’s just not the right location as it gets very tall. Ironweed will commonly grow to 6ft tall (it is called giant ironweed for a reason) but I’ve seen ours get up to around 8ft tall. Essentially to the ceiling level of our front porch. That is one tall plant!

In the late spring I cut it the ironweed by our front porch down which resulted in a shorter plant, only about 5.5 ft tall.

Ironweed uses in the Garden

Ironweed is useful in the garden to help develop a native plant habitat for our favorite pollinators. When ironweed flowers it becomes an amazing pollinator magnet. Numerous types of native bees and butterflies will visit it in the fall making it a seasonally important plant especially when mixed with other fall blooming flowers like goldenrod and Joe Pye weed.

ironweed with Gul Fritillary butterfly

Due to it’s extreme height ironweed is a tricky plant to place in the garden. It’s more useful in a native plant area or wildflower garden planted toward the middle or back of the garden. With it’s height it will tower over most other plants and be easily seen from all angles. Ironweed will self sow freely and is typically propagated by the seeds or through division. I’ve tried cuttings before but they didn’t root very well.

Ironwood on Our Property

Below is a video on building our home and a land tour of the natural areas. I have the video cued to the section on ironweed.

3 Ways to Start Ironwood Plants from Seeds

  1. The best way to start ironwood plants from seed is to plant the seeds in the fall where they can enjoy the changing temperatures and naturally stratify over the winter.
  2. Another way is to sow the seeds in spring. Store the collected seeds in a refrigerator over the winter to satisfy any cold stratification needs. Sow the seeds, press them into the ground or container, and lightly cover.
  3. Winter sowing may be also be great way to easily grow ironweed seeds. Winter Sowing

In the winter ironweed leaves behind a tall stalk with seed heads that can provide some visual winter interest. By leaving the ironweed stalks up in the winter you can provide winter food for the birds.