The Gardeners' World star, 67, took to social media to pen a heartfelt message to his childhood sweetheart Sarah, whom he met at Cambridge University. "We got married 39 years ago today - the picture is a little faded, a little wrinkly, like us but the love is as evergreen and strong now as it was all those years ago," Monty sweetly wrote.
WATCH: Monty Don films inside picture-perfect home with wife Sarah
The throwback photo, taken in 1983, showed the newlyweds standing outside a set of wrought iron gates, with Monty's new wife rocking an unconventional blue outfit. Sarah ditched bridal white for a dusty cornflower jacket with large buttons down the front, which she paired with a chunky necklace and matching earrings.
Meanwhile, Monty didn't appear to have aged at all – he sported the same thick curly hair and big grin, and wore a cream suit and black spotty tie.
Monty marked his wedding anniversary by sharing a throwback photo from their 1983 nuptials
His followers were delighted to catch a glimpse inside his private life, and they rushed to the comments to share their congratulations. "Happy Anniversary to a great couple. Here's to many happy years to come," wrote one, and another remarked: "Happy anniversary! The picture is beautiful and your caption [is] so touching."
A third jokingly penned: "A great achievement in a world bent on destroying relationships, especially with those in the limelight! Well done for keeping your feet well grounded (working with soil helps!)"
The couple share three children
Monty's wedding photo comes just days after he praised his wife for being "entirely supportive" when it comes to work on their Herefordshire garden, Longmeadow.
Chatting on the Gardeners' World magazine podcast with editor Lucy Hall, the TV star said: "Sarah has always been an entirely supportive partner in crime. One of the things I always say privately and I should say publicly at every opportunity, it's her garden as much as mine. This is not my garden, it's our garden. It's 'We' always.
"Every significant decision, and quite a few insignificant ones, are made by the pair of us in agreement and we have this principle that both of us have a veto over everything. It's a very good way to run a system because what it means is, if you disagree, and we do a lot, you can't do it and say 'Live with it.'"
Monty and Sarah share three children, Tom, Adam and Freya, and they are proud grandparents to George and Daisy Rose.
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