Lower feed costs, wide-open space, fewer regulations, family ties and community amenities, according to area economic development officials.
Darin Dykstra, a California dairy farmer who moved to Plymouth County and built Dykstra Dairy, felt the same.
He and his wife Linda and their two sons left California in 2002 and began milking cows at Dykstra Dairy, east of Struble, Feb. 3, 2003.
"It's a good area to have a dairy," Dykstra said. "You're right in the middle of all the feed."
That means less cost because, in addition to the 75 acres the dairy sits on, the family owns and rents about 1,750 acres to grow corn for corn silage, Dykstra said.
On the family dairy in Ontario, Calif., of which he is still a partner, feed costs are higher because they own just 60 acres and the dairy takes up 40, Dykstra said.
"So you have to buy all your hay and grain and everything," he said. "Here we grow our own corn and do it relatively inexpensively because you are putting all the nutrients from your manure water onto the fields as fertilizer."
Dykstra also has other reasons for building a dairy in Plymouth County.
He and his wife graduated from Dordt College in Sioux Center and she has a brother who teaches there.
Andrea Westergard, Plymouth County's economic development director, learned recently at the World Ag Expo in California that Dordt and its roots are a big draw for California dairy farmers.
"The dairy industry is a large Dutch industry," Westergard said. "A lot of the people that we spoke with, their main reason for wanting to come to Iowa was because their son or daughter was attending Dordt College."
Dykstra and his wife also found the Plymouth County site attractive because they wanted to send their children to the Christian school in Orange City.
Westergard had heard similar comments from dairy operators at the expo.
"They're looking for the Christian school atmosphere," she said. "And we have a large availability of that as well."
But Dykstra also had a more personal reason for building Dykstra Dairy -- he completed his senior practicum at Wells' Dairy, in Le Mars, in his final year at Dordt.
"Before I left there (Wells'), the people said 'We would really like to see bigger dairies come out here and supply us with milk,'" Dykstra said.
Throughout the years he always kept it in the back of his mind that maybe someday he would return to the Le Mars area and build a dairy, Dykstra said.
Now he's back and all of the milk produced from his 3,050 dairy cows is sold to Wells' Dairy.
California isn't the only state Iowa recruitment groups look at to entice dairy farmers, but the World Ag Expo opens up doors to a huge population of dairy operators.
About 100,000 people come through the gates each of the three days of the show, Westergard said.
"While we were there we were able to talk to five or six people interested in relocating their dairies," she said.
Iowa Area Development Group representatives attend the World Ag Expo annually encouraging dairy farmers to relocate in Iowa, said Mike Meissen, value-added agriculture vice president of the group.
"We have a tremendous amount of folks coming to Iowa," Meissen said. "We truly have people visiting Iowa 12 months of the year."
The Iowa Area Development Group is a consortium of 28 Rural Electric Cooperatives and 128 independent telephone companies across the state, Meissen said.
Bringing dairies to Plymouth County and Iowa means huge positive economic impacts, Westergard said.
"Dykstra Dairy's annual tax base is $62,856," she said. "Every dairy you can get into your community, if you multiply that times as many..."
There are currently 6,900 dairy cows in Plymouth County, Westergard said.
Most of those animals are at Dykstra Dairy and Plymouth Dairy Farms Inc. but there are two or three small dairy farmers in the county, she said.
Iowa supports more than 2,000 dairy farms, more than 217,000 dairy cows, 22 dairy processing companies and 3.86 billion pounds of milk are produced annually in the state, Westergard said.
The economic impact of 500 cows in Iowa in total sales beyond the farm equals 28.2 jobs created and 1,900 acres of Iowa crops and resources used, Westergard said.
"When we put dairy cows into a county, the annual economic impact ranges between $15,000 and $17,000 per cow per year," Meissen said. "We don't call them dairy cows -- we call them economic engines."