Prime position: Open Garden Squares weekend opens London's finest private gardens but houses nearby have the keys year round

The annual summer Open Garden Squares Weekend has become a favourite with Londoners. There are events and tours, art shows and cycle routes for all the family across 27 boroughs and at some extraordinary venues, from rooftop gardens to hidden historic city courtyards.

This year more than 200 green spaces across the capital are taking part, some usually closed to the public — such as the gardens of No.10 Downing Street.

Scores of central London garden squares, defining elements of the city’s architectural heritage, are on view. In all sizes, they offer some stunning displays.

Stroll through these private spaces and house hunt while you are at it. Open to you specially for the weekend, one of these squares could be open to you all the time if you buy a home nearby with residents’ access.

Here’s our choice of gardens and the properties you could buy.

FOR COMMUNITY SPIRIT: GLOUCESTER SQUARE, HAGGERSTON

Gloucester Square in Haggerston was originally lined with cottages for workers at nearby factories and gasworks, but after the Blitz they were pulled down and eventually replaced by slightly boxy Eighties affordable housing.

Three decades — and Right to Buy — later, and most homes in Gloucester Square are privately owned. In 2009, these owners got together to agree something had to be done about their communal garden which, through lack of both funding and effort, was a semi-jungle.

Today the gardens are a treat. Residents have split the space into several zones including a woodland area, a cottage garden and play area. To save money they did as much of the work as possible themselves and grew most of the flowers from seeds or cuttings.

Thanks to their location and era, the homes in Gloucester Square are, by garden square standards, pretty affordable if not desperately pretty. A two-bedroom house would cost about £600,000 to £650,000, and a three-bedroom house about £750,000 to £800,000.

As well as the garden, Gloucester Square has a great location close to Regent’s Canal, Broadway and Columbia Road markets and Haggerston Park. Haggerston and Hoxton Overground stops are nearby.

FOR HORTICULTURE: LEXHAM GARDENS, SOUTH KENSINGTON

In the Eighties developers wanted to replace Lexham Gardens’ green oasis with an underground car park. Salvation came from local resident Sir Cyril Taylor, businessman and adviser to Margaret Thatcher, who stepped in to buy the freehold of the Kensington garden from under the developers’ noses for £71,000, then redesigned it.

Small, at one acre, but perfectly formed and cleverly planned, the gardens are set out in six zones, with a social area with two ponds, a gazebo and benches, a quiet reading area with lawns, a shrubbery, a main lawn with a bronze statue of a horse, a children’s playground, and a rose garden. The garden is now owned by a trust held for the benefit of residents.

Will Allen, associate partner at Strutt & Parker, says the vast majority of Lexham Gardens’ four- and five-storey townhouses have been converted into flats, and that there is a significant premium to living on the east side of the street with access to and views of the gardens.

A two-bedroom flat overlooking the gardens would cost about £1.5 million, he says, while a similar property on the west side, with no garden access, is about 10 per cent cheaper. In this kind of market location really matters, right down to the floor you are on.

“The first floor is the most expensive, with amazing ceiling height and floor-to-ceiling windows,” says Allen. “Some of the buildings don’t have lifts, so flats on the fourth and fifth floors are cheaper, because it is quite a walk up.”

FOR ECO-CREDENTIALS: KENSINGTON GARDENS SQUARE

This Bayswater square takes the environment seriously, from lobbying the Government to act on plastics recycling, to collecting horse manure from nearby Hyde Park stables to use as fertiliser, to composting and recycling all the garden’s fallen leaves and lawn clippings.

Worm farms have been installed to keep worms safe from predators — allowing them to breed in peace fed on a diet of residents’ kitchen leftovers — bird boxes are dotted around on trees, and there are plans to add bat boxes.

Another big selling point of Kensington Gardens Square is its five- and six-storey mid-19th century houses, many now flats. “They are the classic, traditional stucco-fronted Bayswater properties with pillars around the front door,” says buying agent Oli Russell, head of search and acquisition at SP Property Group. “What is particularly nice is that the first and second floors have attractive ornate arched windows.”

An 850sq ft two-bedroom flat in the square would cost between £1.25 million and £1.75 million, and Russell says that the upper flats tend to be the province of young professionals, with the larger flats on the lower floors taken on by families willing to forgo a private back garden because of the garden square.

FOR SOCIAL LIFE: CLEVELAND SQUARE, BAYSWATER

The residents of Cleveland Square, Bayswater, really make the most of their outdoor space, from alfresco film screenings when residents bring blankets, cushions, food and drink, to children’s parties, plus a massive annual summer bash with a DIY barbecue, communal tables, music and ice bins for chilling drinks.

They have also taken part in Shakespeare in the Square, with open-air performances of classic plays, hosted one-off concerts and on fireworks night go all out with a fantastic bonfire and fireworks display set to music.

The square itself is a beauty, lined with Grade II-listed Victorian terraces, and with one-and-a-half acres of gardens that include a dedicated play area where parents — and of course nannies — make friends with their neighbours.

Cleveland Square is also well positioned for Paddington and the imminent arrival of Crossrail, and Marcel Zaidan, director of Dexters estate agents, points out that having Hyde Park on the doorstep is another huge plus. “It is also a particularly well-kept, manicured garden square which people like, too,” he says.

Prices on the square range from around £485,000 for a studio flat to around £1.25 million for a two-bedroom property, while Zaidan is currently selling a four-bedroom maisonette with basement swimming pool for £6 million.

There are virtually no full houses left in Cleveland Square, he says. “If you found one it would go for tens of millions. The market is fairly static right now. Stamp duty means that at the more chunky prices, properties will stick a bit.”