"I love the fact she even grew the impressive peaches in the photo," he added.
Amid the celebrations, Clarence House's Instagram also shared a post that read: "Thank you for all your kind messages and well wishes on The Duchess of Cornwall’s 75th birthday today!"
Royal fans were delighted over the release of the stunning photos, with one fan commenting, "She is more beautiful than ever."
Another penned: "Happy Birthday Ma'am. Love & regards from Germany. May your new year be blessed with health, happiness and fulfilment! By the way... that's such a lovely picture!"
"Happy Birthday Your Royal Highness. May your special day be blessed with all the good vibes you spread out into the world. Wishing you happiness and joy," added a third fan.
It follows the Duchess of Cornwall marking her milestone birthday by guest editing Country Life magazine's July issue, where the Duchess of Cambridge showed off her talent in taking the cover photo for the special occasion.
It was quite the family affair for Camilla, whose son - food writer son Tom Parker Bowles - wrote about his mother's favourite dessert, peach melba.
“My mother is a keen grower of white peaches (the subject of this month’s column was very much her idea),” Tom said.
It's been a busy few weeks for Camilla, who also recently appeared in a one-hour ITV documentary, Camilla's Country Life.
She also gave insight into family life in an interview with the Daily Mail, where she spilled that she has embraced the social media world of TikTok thanks to her grandchildren. She also spoke of how family meals are a thing of the past, and everyone is now on “their devices”.
WATCH: Camilla, Duchess of Cornwall's cheeky joke to The Crown actress who plays her
“Families don’t sit down any longer, do they, and have dinner," she said.
“Because I am ancient, in the old days we all sat down (to eat). Now everyone is on their devices. It just makes me quite cross.”
Camilla previously told British Vogue that her birthday will be a low-key event.
"There won't be much celebration," she said. "I shall spend it with my family and a few friends."