They bloom every other year in autumn, coating lawns in hues of red and white, withstanding droughts, downpours, and frost. All that politicus perennis needs to thrive are unshakable opinions and plenty of exposure to the sun, or at least a well-traveled road. They may not be rare, but do not try to pick them, or you will get arrested.

The election is coming, and that means that campaign yard signs are about to become as ubiquitous and annoying as kudzu. Although it often feels like they just sprout from the ground every September, there is an entire universe of businesses making sure that no election has to go into the grand finale without its accessories.

You do not learn how to be a sign-maker — you are born one. At least, this is the impression you get after talking to a few of them. Their websites are spackled in words like “second-generation” or “fourth-generation,” and most of the employees have the same name. As a result, each sign-maker also functions as a sign historian, able to chronicle all the ways in which the industry has changed, even if the signs look the same.

No one is quite sure if campaign signs do anything, or simply function as the inflatable yard snowmen of the election season. Regardless, the season for signs picks up in late August and runs through mid-October. Candidates in local races usually order around 100 signs, while state and national candidates might order thousands — and the candidate who only orders 10 signs might get made fun of at the shop afterward. After November, the political sign jobs evaporate, replaced by t-shirt orders or commercial work for ad agencies. Twenty-nine-year-old Samantha Briggs at Kirk Briggs Signs, Inc. in Northern California says her dad compares the campaign sign business to date farming: “Every two years, there’s a great big harvest.”

Keller Bros. & Miller, Inc. in Buffalo is celebrating its 100th anniversary in 2016. The walls of its building, owned by the Salerno family, are covered with vintage campaign signs. The oldest comes from a supervisor’s race from 1916, but the one that gets the most attention is from John F. Kennedy’s 1960 presidential bid. It was the biggest campaign sign order the business ever had. The Salernos don’t do much campaign sign work anymore, though; direct mail is where the money is. “People buy signs from big-box stores online now,” Ralph Salerno says. Glenn Tamblingson, who has been making signs at Campaign Graphics since 1983 and does landscape photography and tours of the Grand Canyon when not in election mode, is not impressed with direct mail. “It’s our nemesis. Consultants make money on direct mail, but not on signs,” he explains. He defends signs as the better — and more cost-effective — choice. Direct mail ends up in the trash, while with signs, “you have to look at it while you’re driving whether you like it or not.”

Like everything else that has to do with the printed word, the sign business has been radically changed by the internet. Suddenly, sign shops that could depend on election income were competing with shops online that keep driving down prices and shipping across the country. Gary Barzella, a chemical engineer who says he ended up in the sign business by accident 31 years ago, has tried to adapt by going native online. Google “campaign signs” and his website comes up as the third result. His business, based in Wisconsin, is named Cross & Oberlie. His website is the far more search-friendly politicallawnsigns.com.

Ralph Salerno’s dad, John, thinks the decline of unions has also hurt the campaign sign business. “The [union] AFL-CIO doesn’t go after candidates when they don’t use the union label anymore,” he says. Frank Ozanski at Clear Images in Ohio adds that being a union shop still helps him attract candidates. Being in a swing state might help too. Orders for Hillary Clinton swag have been coming in like crazy, but he has also made Donald Trump signs (which have been hard to find in many other parts of the country). “I don’t say no to nothing,” he says. When he was asked whether he was going to vote for Barack Obama or John McCain in 2008, he responded, “Whoever buys the most signs.”

Even as the method of selling and making campaign signs has changed, evolving from woodblock to silk screen to digital printing, the look has mostly remained the same, although they might be more weatherproof nowadays. Wade Swormstedt, executive director of the Foundation for the Advancement of the Sign Industry, can unwind an impassioned defense of the sign in general when prompted. “A lot of people completely dismiss the notion that a good sign is designed,” says Swormstedt, whose brother works at the American Sign Museum, and whose cousin is the president of a media group that produces Signs of the Times magazine. “It’s an art form. It’s not just slapping some Helvetica letters on a piece of vinyl.”

Unfortunately, this ringing endorsement of the golden age of signs does not extend to campaign signs, the floppy disk of the industry. “They’re all the same,” he says. “‘Vote for Smith.’ I don’t think design is much of a factor at all.” The standard sign is 18-inch-by-24-inch corrugated plastic, designed to last three or four months before retiring to the trash. (Although one New York Times reader found an afterlife for her lawn signs in 2006: “The metal frames are very useful in the garden, holding frost-protection cloth over early plantings.”)

Other sign experts agree. “In my world, big, bold, and ugly is effective,” Ralph Salerno says. “I get signs designed by ad agencies, and I look at them and go, ‘Wow, this is pretty, but nobody’s going to read it.’ I always tell candidates, when you’re riding down somebody’s street at 30 miles per hour, there’s no way anybody’s going to read everything that’s on your sign. I learned at a very young age from my dad that it’s not the design of a sign; it’s all about getting the candidate’s last name as large as possible.”

The speed of the hypothetical car racing by the hypothetical sign in these examples sometimes changes, but the advice remains the same. “You have to be able to read it at 55 miles per hour,” Ozanski says. “I call it the 50/50 rule,” says Tamblingson. “You have to be able to see that last name and what they’re running for at 50 miles per hour from 50 feet away.” The importance of the last name is paramount, except in very rare scenarios. Tamblingson did signs for Jeb Bush’s first gubernatorial runs, and thinks he may have been the first to print the signs pairing his first name with an exclamation point. “If you’re not a Bush,” he says, “that wouldn’t work.”

Nearly every single sign ends up featuring lots of red or blue. Putting faces on the sign is discouraged, as it’s not going to help voters find your name on the ballot. The only rule more important than making the last name as big as possible, says Swormstedt, “is GET. PAID. UP. FRONT. Good luck after the campaign’s over and the candidate didn’t win.”

The desire for beautiful signs that go beyond last names rendered as large as possible sometimes ends comically. Ozanski did one sign for a school tax levy ballot measure that concerned a school with an eagle mascot. The sign featured our majestic national bird with a tear in its eye. “It was terrible,” he says. “People were like, ‘Are you kidding me? A crying eagle?’”

The sign-makers are all aware of the research disputing that campaign signs have any use besides disturbing your yard’s feng shui, and unsurprisingly still think this sometimes profitable subsection of their profession has meaning — just maybe not as much in a presidential year, when the names are all familiar. The lowly campaign sign is the champion of the newcomer running for coroner, or the council hopeful challenging an incumbent. If you know nothing about the town judge race but do know that your neighbor is always wrong and happens to have a sign featuring one of the candidates, you know enough to vote for the other person. Midterms are where there’s money to be made, and everyone’s desperate to grab your attention for just one second on your way to work to say, “Hey. Here’s my last name. Tuck it in the back of your mind, and pick it come November even though you know absolutely nothing about me.”

If it doesn’t work for these local candidates, this is one superstition that has kept people in business for generations. The Salernos are willing to be a good luck charm; John says that repeat customers “would think that we were part of their success. I used to tell everyone we only print for winners.”