If you decide you want to plant a roadside area, you'll need to find out if the city, county or state had jurisdiction over your site. Contact your state highway department for information on the state wildflower planting program. What has worked? What hasn't? Asking these questions first can save you time and money.
Arrange a meeting with the area supervisor. Ask what the vegetation management program is. Will they defer mowing until after the seeds have matured? Do they spray herbicides that could kill your plants? Who is responsible for maintaining the site after planting? Find out what maintenance is planned before you plant. You don't want to waste your money planting seeds that will be killed after germination or that will be mowed before they're able to set seed. If you can provide seeds, many states will help with planting and management. Some states even offer cost-sharing or other funding programs..
Select eight to ten indigenous species that will provide a blooming period of at least two months and include annuals and perennials. Native species often prefer the poor soil that occurs along roadsides. However, it's best to choose a site that is relatively free of road salts, motor oil, competing vegetation and construction activities.
You'll want to pick a highly visible site for the planting, such as a rest area, traffic interchange, park turnout,or the approach into town and you'll want to choose species that will be visible at 55 miles per hour. Bright splashes of color are more important than individual plants. Plant wildflowers at the recommended rates, concentrating on smaller, denser areas rather than on larger areas of sparsely planted flowers. Remember that plantings covering one linear mile may be too ambitious!
Existing vegetation at the site shouldn't be a tight turf. The ideal turf would be warm-season, clump, or bunch-forming grasses, but many states have planted cool-season grasses such as fescue or ryegrass on roadsides, which compete with interseeded wildflowers. Areas where cool-season grasses occur may have to be periodically replanted with wildflower seeds.
Watch out for newly constructed highways, whose shoulders are prime sites for wildflower planting projects. Seeds germinate more readily in loose soils than in hard, compacted ones. If you plan far enough ahead, the highway department could plant grasses that will be compatible with wildflowers when they plant along new roadsides.
Ask if your highway department, which probably owns a flail mower or other equipment that lightly scalps the ground, can prepare the ground for you. Leave the plots staked so you can monitor them over a three-year period. Knowing which species worked and which didn't will help you decide what to plant later.
Be sure to use signs to call attention to your wildflower area. You want everyone to know your group made this beautiful area possible and to remind road crews that they need to treat the area with care.
Unless you are independently wealthy, you will have to seek funding for your project. You could ask civic or fraternal organizations to donate money for seeds or adopt a section of roadway for highway plantings. You might persuade local businesses to "sponsor a species" and donate money to buy seeds. Check with foundations in your area. Some are willing to donate funds for highway projects. Native plant nurseries are also willing to donate seeds and funds for worthy projects.
Oklahoma City Beautiful, Inc., wins the prize for most original wildflower project fund-raising idea. The group held a contest for the most unique penny-collection canister and put the canisters in shopping malls throughout the city. Money collected in the canisters paid for roadside plantings that have pleased visitors and residents with vibrant colors.