With the large drifts of purple and gold wildflowers blooming along area roadsides, it seems even nature is celebrating LSU football.

“Fall and spring are when Louisiana wildflowers are at their peak,” said botanist Charles Allen, retired professor and co-author of "Louisiana Wildflowers Guide."

From your car window, you've probably seen the swamp sunflowers because they grow tall between August and November. They sprout up in ditches and fields and along the edge of forests.

Goldenrod, reaching heights of 10 to 12 feet, is another showstopper. It has been accused of causing allergy problems, but Allen said it’s pollinated by bees, wasps and butterflies, so very little pollen is in the air, meaning you probably aren't breathing it in.

“Ragweed and grasses are usually the cause (of allergies), since so much of their pollen is in the air for wind pollination,” he explained.

When it comes to purple, tall ironweed is an eye-catching flower, as is the sky-blue mistflower, sometimes called wild ageratum, which grows in moist meadows, woods and disturbed soils. It has been identified in 22 parishes.

Most of the roadside wildflowers are perennial, meaning that, once established, they grow back year after year.

“What kills these plants are the herbicide sprays used by parish highway maintenance programs,” Allen said.

If, instead of spraying them with chemicals, the vegetation was cut only once a year, "we’d rival Texas in the wildflower display," Allen said.

Annual cutting would also help ecosystems and provide habitats for pollinators, he said.

Brandie Richardson, public information officer for the Louisiana Department of Transportation and Development, said the agency does try to take the wildflower-growing season into account before spraying or cutting highway roadsides.

However, visibility and safety are "our No. 1 concern,” she said.

The state divides each parish into districts, and each district decides the mowing and spraying schedule, she said.

Richardson said DOTD does have a wildflower program, and you can be part of it by helping to catalog the plants you see by logging in the information at apps.dotd.la.gov/operations/facilities/wildflower.aspx.

Louisiana also has a wildflower seed bank project, a cooperative endeavor between DOTD and the University of Louisiana at Lafayette. Wildflower seeds are collected and stored at the UL Experimental Farm near Cade. The seeds are harvested and stored there, then planted along state highways.

If you'd like to grow your own patch of wildflowers, fall is a great time to plant. Check with local nurseries for seeds that will bloom the first year. The established plants must be allowed to drop their seeds after blooming before they are mowed.


Louisiana Master Naturalists of Greater Baton Rouge seeks to advance awareness, understanding and stewardship of the natural environment. For more information, email info@lmngbr.org.