Why was 3-year-old Sadie Greenstein spending her Saturday morning surrounded by beetles?

"So she could be cute with the ladybugs," said Sadie's father, Joel Greenstein, as she crouched to get a closer look at one crawling on the ground.

That seemed to be the consensus at Magnolia Plantation and Gardens on Saturday, where children were invited to help release 150,000 ladybugs throughout the grounds.

"They're like a natural pest control," said Tori Luke, the plantation's youth program coordinator. "They eat aphids and scale insects and other sorts of harmful bugs. So if we introduce these ladybugs into the gardens, it helps keep our plants healthy."

About 70,000 of the beneficial beetles were released last year at Magnolia Gardens' first ladybug event, which Luke said was, to her surprise, not enough for the droves of budding entomologists who came out. So this year, the number was doubled.

"It looks like that was a good idea," she said, gesturing at the crowds who filled the grounds.

Some children, like 2-year-old Lillian McMullan, came decked out in red, black and polka dots for a costume contest. Lillian accessorized with white sunglasses and a well-worn bean bag ladybug, which her mother, Candice Herriott, said she brings everywhere.

"Her favorite thing is ladybugs, since she was like 3 months old," said Herriott, who lives on James Island. "When we heard about this, we had a dozen friends calling us and forwarding us the link and making sure we knew about it. Of course we had to come. We've been talking about the 'ladybug party' all week."

Luke said she hadn't seen any kids who were scared of the insects.

"It's funny, because a lot of kids either love or hate bugs ... but ladybugs seem to be the world's favorite insect," she said. "They're cute and they mean good luck, so a lot of people aren't scared of them, which I find interesting."

This was certainly the case for Lillian when she was given a small cup of her favorite animal to release.

"She loved them!" said Herriott. "She was trying to get them on the leaf, and they were taking their time, so she started shaking them onto it."

Other children ended up with more ladybugs on themselves than in the flowers, but they didn't seem to mind. "They tickle!" was a commonly heard exclamation.

The ladybugs had been held in a cool place Friday night to make them less active, which Magnolia zoo curator Chris Smith said would help them adapt to their surroundings more easily.

The zoo and other wildlife and conservation groups were on hand to talk to kids about the environment and introduce them to an array of animals, from a red-shouldered hawk to 6-foot boa constrictor named Marilyn.

"We just want to help bring out an appreciation of nature and help the kids understand that every animal has its place in the environment," said Smith.

Kristin Hackler of Johns Island said she loves visiting the plantations, and the ladybug release was extra motivation to bring her 18-month-old son, Edward.

"He was fascinated - letting them run up and down his arms and around his neck," she said, as Edward inspected an African spurred tortoise. "He's touched every single animal here, just about. Every time there's a petting exhibit or something like that, he just likes to pet them and play with them, and he's always very gentle."

Edward went on to win first place in his age group for his "gentleman bug" costume, which included an antennaed fedora.