Butterflies are in trouble. It doesn't take much to help

New research shows butterfly populations have fallen dramatically over the past two decades, but there’s a lot you can do to help these fluttering flower-lovers, even if all you’ve got is a single pot on a porch.

“You can really make a difference to the local population. Any individual flower you put out it likely to get visited,” said Nick Dorian, a post-doctoral researcher at the Chicago Botanic Garden who studies butterflies.

All it takes is planting a few flowers and avoiding insecticides.

Here’s what to know:

Butterflies are taking a dive

Researchers across the United States collected data on more than 35 butterfly monitoring programs. It included data from 12.6 million individual butterflies comprising 554 species taken in 756,957 surveys.

The results were worse than they expected.

"They are all in trouble, everywhere," said Collin Edwards, an ecological modeler with the Washington state Department of Fish and Wildlife and first author on the paper published in the journal Science.

The chief causes of the decline include habitat destruction, a drier and hotter climate because of climate change and insecticide use.

This is where humans come in ‒ because it doesn’t take much to plant a butterfly haven. All the insects need is nectar from flowers and places to lay their eggs, which just about any yard can provide.

No in-depth research is required, said Elizabeth Crone, a professor in the Department of Evolution & Ecology at the University of California Davis and one of the authors of the paper documenting the decline of the much-loved insects.

“I just look at what flowers the bees and butterflies are visiting in the garden center. Then I buy those plants and plant them.”

Milkweed, the preferred food of monarch butterflies, gets all the press but almost any flower is great, and lots of herbs as well.

They don’t have to be exotic. Golden Alexander, Zinnias, Mexican sunflowers, Cosmos, Snapdragons are all big nectar producers.

“You don’t need the champagne of pollinator flowers – Miller Light will do,” she said.

Get to know your local butterflies

There are probably more butterflies flapping around your yard than you realize.

If you have the time and the inclination – perhaps with a cool drink or while you listen to a podcast – spend some time in the warmer months just sitting near your plants to see what drops by. In 10 or 20 minutes you’re likely to see visitors.

“It can be easy to think ‘I don’t see any butterflies in my garden’ because you glanced a few times throughout the day. But actually, there were 10 butterflies there today, Dorian said. “The butterfly might only stay for 90 seconds, but that's all it needs to get a nice meal from your flowers.”

A quick online search for “local butterflies” in your area should provide all the images you need to name these callers to your garden.

Spending time with the flowers will also let you know what to plant more of next year. “They’ll tell you what flowers to keep growing," said Atticus Murphy, a postdoctoral researcher at UC Davis who helped Crone write a guide to pollinator gardens.

If you plant it, they will come

You don’t have to worry whether butterflies can find your flowers, say experts.

Butterflies spend their time flying around searching for food and all it takes is a colorful display to attract them.

“They have pretty good eyes for pursuing color. They fly high up and look around,” said Dorian.

Some species also have an excellent sense of smell. Monarchs can sniff out a milkweed plant from a football field away.

That means they’re able to piece together separate flowers over a fairly large area to get the nectar they need.

So you’re not responsible for providing all their needs, it’s all about the broader area, said Crone. “And if you’re the first, that’s a great start.”

Every bud helps

For those without yards, there are many pollinator-friendly plants that do well in containers. Herbs are good, if they’re allowed to flower, as are flowers like anise hyssop, purple coneflower and swamp milkweed.

The nice thing is that butterflies want the same thing as humans. “We like a big diversity of colors, we want beautiful showy flowers,” said Dorian.

The movement to plant butterfly gardens has really taken off in the past decade.

“It’s incredibly exciting to see so many people taking an interest in conservation,” Crone said. “Nature isn't someplace you have to go to, it’s all around us.”

Given the doom and gloom about the environment these days, it’s nice to make a difference, she said.

“When you plant a garden, it becomes a little easier to have hope,” she said. “It’s such a powerful antidote.”

This article originally appeared on USA TODAY: Butterflies are disappearing. Even the smallest garden can help