The promotion came in the midst of a rare cold spell, as Harper - hitting .250 with three homers and 13 RBI this month - had gone 0-for-12 with five strikeouts in a home series against Palm Beach.
Harper was with Binghamton last September, hitting .247 with seven home runs, but was sent back to St. Lucie so Mike Jacobs could convert from a catcher to a first baseman.
"There was disappointment; I'd be lying if said there wasn't," Harper told Inside Pitch. "I went home and my dad (former Major Leaguer Brian Harper) said, 'Hey man, you've got two options. You can quit, or you can work harder.'
"At first I felt like I'd rather quit, just as a natural reaction from the disappointment of being demoted. You never feel like you're going to want to do a level over again. But I got into it and just said that I was going to work even harder this year; obviously the Mets like me and they're giving me a chance to play."
Ragsdale, 22, has improved offensively this season after hitting .193 in four previous minor league campaigns.
He was hitting .260 with 10 homers and 38 RBI for St. Lucie at the time of his promotion, and had strung together an 11-game hitting streak in which he'd raised his average 24 points.
"In past years, I was always trying to find a swing that worked for me," Ragsdale told Inside Pitch. "This year, I finally found what works for me, so now I go to the batting cages and just try to maintain the swing that I do have. It's been pretty cool not to be searching for some new swing all the time."
In a related roster move, infielder-outfielder Chase Lambin was promoted from Binghamton to Norfolk (AAA) of the International League, his second trip back to the Tides in two weeks.
Lambin hit .421 with a double and two RBI in six games for Norfolk from June 18 through June 23. He was hitting .331 with 14 home runs and 29 RBI in 53 games for Binghamton.