As summer approaches, several Maine farms are preparing for groups of campers who will spend their days at farm camp working with animals, gardening, exploring nature and hopefully getting some dirt under their fingernails, too.

“Our motto is hands in the dirt fun,” said Holly Sheehan, co-director of Farm Camp, a 12-year-old environmental literacy program with farm locations in Cape Elizabeth and Wiscasset. “Our campers are outside for pretty much all day. They’re building forts, fairy houses, catching frogs, feeding sheep, collecting eggs and seeing nature firsthand. I think kids like being outside and having free play as well as structured play and just being immersed in nature is pretty powerful.”

In just a couple of decades, day camps at Maine farms have gone from being an unusual niche summer option to something offered by more and more farms. The camp programs differ around the state, depending on the size and focus on the farm. But the farmers and program leaders all seem to pride themselves on offering kids the opportunity to experience Maine farms for themselves. This kind of hands-on learning is good for youth and good for the continued renaissance of Maine agriculture, according to Walter Whitcomb, the commissioner of the Maine Department of Agriculture, Conservation and Forestry.

“Farm camps, 4-H, [Future Farmers of America] projects, school gardens and other agricultural-related programs and events are excellent ways for young people to learn more about plants and animals,” he said Thursday. “Like teachers in traditional classrooms, the leaders of farm camps help children see the real-world application of science on small Maine farms. To continue the agricultural resurgence underway throughout Maine, we all have a shared goal of introducing children to agriculture, farm life and where their food comes from.”

Years ago, farm camp was a harder sell to parents and kids. But that’s changed, according to Linda Hartkopf, who runs the organic Hart-To-Hart dairy farm in Albion. She said this week that when she and her husband, Doug Hartkopf, started their camp program 18 years ago, it was more of an experiment.

“We started with six boys and built from there,” Linda Hartkopf said. “It’s definitely growing. I think in the last couple of years I haven’t even printed out brochures. It’s completely by word of mouth, and I was full back in February and March. The kids sell it, the parents sell it. That’s really how it’s grown. It’s kids going back and saying what a great time they had and parents excited about the authenticity of what the kids are learning.”

One of the newest farm camps in Maine is taking root at Toddy Pond Farm, a 500-acre diversified family farm at the end of a long dirt road in the rural Waldo County town of Monroe. Farmers Heide and Greg Purinton-Brown said they started thinking seriously about adding a farm day camp program after having good experiences offering farm stay vacations, in which families and other travelers immerse themselves in the day-to-day operations, sights and sounds of the farm. The Purinton-Browns also have had a good time participating in the Maine Open Farm Day program, which this year is scheduled for Sunday, July 24.

“With Open Farm Day, we saw a lot of parents come with their kids, really engaged and enjoying the animals and the farm,” Greg Purinton-Brown said.

Heide Purinton-Brown said the farmers benefit from such visits, too.

“It’s really fun to have that energy on the farm,” she said.

Their new farm camp program will be open to children ages 6 to 13 and will be led by Jasmine Fowler, a home-schooling mom with a degree in early childhood education and family studies. Fowler and Heide Purinton-Brown are sisters, and Fowler comes every week to do farm chores with her 10-year-old daughter, Juniper.

“Juniper asks awesome questions,” Fowler said. “She’s learned a ton.”

This week, Juniper gently cuddled a squirming piglet as its mother waddled off to eat a snack. In the distance, freshly shorn sheep grazed and gamboled in a grassy field, and a flock of curious chickens ranged around the farmyard. It was just another day on the farm — the kind of day the farmers here are hoping to share with many more children this summer. They hope the campers will learn where their food comes from, learn about sustainable practices and, of course, experience the sights, sounds and smells of a farm.

“It would make me happy if a child went to this camp and went home excited about anything they saw or did here,” farmer Greg Purinton-Brown said.

Hartkopf, the dairy farmer, said that every summer, the farm camp kids most enjoy doing the farm chores, working with the animals, playing on the hay bales and exploring the pond.

“But we weave in many different aspects,” she said. “I have told some parents I’d love to be a fly on the wall, to hear some dinner table conversations after farm camp. We handle a lot of topics. We talk about the circle of life. We talk about life and how interconnected we all are.”

And everything the kids do, from helping train animals to getting stuck in the mud in the pasture, helps them have a true farm experience.

“They have endless stories, and that’s what they’ll carry with them,” Hartkopf said. “That’s something that’s real and is a part of who they are.”