All hail His Egg-ellency!

King Charles III visited an urban farm in Harlem and happily fed a flock of chickens, toured a veggie garden and discussed mushrooms during a rare trip to the Big Apple Wednesday.

The British monarch, 77, flashed a grin as he tossed lettuce to hungry hens alongside children at Harlem Grown, a community group that turns city lots into sustainable farms.

“I gave him the little leaves for the chickens and he fed them. I’m pretty sure he had fun doing it,”  Alana Schira, 12, who helped the king feed the fowl on West 134th Street near Malcom X Boulevard.

“He’s so nice, very respectful, not what you’d expect from a king – but in a good way,” said Eliana Hutson, 13.

“We were just talking about the garden and everything, all the important things that are going on with homegrown stuff. It was shocking but also thrilling at the same time.”

Others said His Majesty seemed truly excited to learn about harvesting his own food.

“It was a surreal experience,” Harlem Grown CEO Tony Hillery said of the king’s visit. “He asked the right questions, he was engaging, he was part of the process. My brain is still spinning.”

Charles hasn’t hopped across the pond to New York since he toured the Big Apple with his late mother, Queen Elizabeth II, in 2007. 

“He was really kind, generous, excited to talk to the children and learn about the produce,” said Jocelynn Ricard, of Genesis Companies, an affordable housing developer that partners with the Harlem group.

“Harlem Grown has mushroom chambers that they grow in the basement of one of our buildings, and we spoke a little bit about that. He was really interested to know what kind of mushrooms, and I believe it was portobello mushrooms. He was very knowledgeable,” said Ricard.

“He wanted to know if we use sawdust and coffee grinds. He wanted to know the method,” she added.

Meanwhile, his wife, Queen Camilla, toured the New York Public Library with actress Sarah Jessica Parker and Anna Wintour of Vogue magazine.

Camilla, 78, was chummy with actress Parker as they toured a specially curated selection from a collection marking America’s 250th anniversary.

She and Parker were shown books and documents with ties to both the UK and the US, including a copy of the Declaration of Independence and a letter from English author Jane Austen.

Camilla swooned over a copy of “Now We are Six” by A.A. Milne, who penned the original “Winnie the Pooh” books.

“Oh! Favorite, favorite, favorite!” the queen gushed, as she was told the book contained some of the first drawings of Roo the kangaroo, by illustrator E.H. Shepard.