It goes without saying that a man who has won prizes at every Highgate Horticultural Show for the past 20 years might be reluctant to surrender the secrets of his gardening success.

But Alan Dallman, chairman of the Highgate Horticultural Society for 12 years, has decided to share a few of his most lucrative tips for a beautiful, award-winning garden with Ham&High readers.

“Most gardening is common sense,” says the 76-year-old, of Wood Vale, Muswell Hill. “If you are raking up leaves, even on pathways, use a rotary mower.

“If you have squirrels after your bulbs, put hanging basket frames over them and that will keep them off.

“And if you can make your own compost, it is much better for the soil and you will see results, and you can save a lot of money doing it.

“There’s no real secret, it’s just a lot of hard work, but it makes it worth doing.”

Mr Dallman’s love of gardening started early. As a five-year-old he was tending his own plot in his father’s garden, and he has visited the Chelsea Flower Show every year since he was 14.

He and his wife Anne purposefully bought their home because it had a very large garden for a property in London – three quarters of an acre.

“I don’t like a set garden,” Mr Dallman said. “I like a garden looking the way that nature meant it to be. Our garden isn’t structured, it’s all natural.”

They have opened their garden to the public for 27 years during National Gardens Scheme Open Gardens but take a break from showing visitors around this year.

In 2010 and 2013, the London Gardens Society awarded them best large garden in London and the couple received a visit from Prince Edward, the Earl of Wessex and a society patron, last summer.

“I suppose if you put gardening down as a hobby, you generally put all you can into it, don’t you? That’s what I do,” Mr Dallman says.

“It’s about having an interest in seeing things grow and in nature, but you do have to know what you’re doing.”