Kiwi couples are lining up to get married in this living, breathing, green church in the Waikato.

You'd think that with a passion for trees and an encyclopedic knowledge of them that Barry Cox would have enjoyed a long career in arboriculture.

Not so; before the age of 10 (too young to understand the criteria required for the top job at the Vatican), Barry wanted to be the Pope. Instead, he settled for the revered position of head altar boy in his home town of Shannon, in Horowhenua.

1 of 4 The gate to the church came from Barry's family farm in Shannon. 2 of 4 Alnus glutinosa 'Laciniata' winds its way over the temporary roof frame. 3 of 4 Deciduous trees put on a stunning autumn show. 4 of 4 Scruff the dog enjoys a drink from the pond.

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Barry thinks his appreciation for the architecture and pomp and ceremony of churches stems from his Italian ancestry. He fed this interest over many years touring New Zealand, Europe and America, often on a motorbike, studying the proportions, angles, heights and pitches of church roofs, walls and porticoes.

After planting more than 4000 trees on his 90ha dairy farm in the Waikato, Barry finally settled on a flat 1.2ha property near Cambridge. With a blank canvas, free-draining sandy loam and Mount Pirongia rising majestically in the distance, the climate, location and soil were ideal for growing specimen trees.

RAY DIXON/Cloudcutterphoto.co.nz The spherical Acer platanoides 'Globosum' and low camellia hedge surround the structure.

Connecting his love of trees with a desire for an income, Barry started Treelocations, a business that moves large trees (up to 6m tall) using a specially designed tree spade – a huge machine that resembles an apple corer. Mounted on the back of a truck, it works by digging down and under the tree to scoop up cleanly the whole plant, including its vast root ball.

There are only three such tree spades in use in New Zealand. "People know how much I love trees," says Barry, "so they call me when there are trees that would otherwise be cut-down or removed. I go and kind of rescue them."

Rehoming semi-mature trees has enabled Barry to accelerate the landscaping of his own property, giving it the look of a project 20 years in the making rather than just four years old.

Trading trees, growing and moving them for clients deepened Barry's connection and knowledge of them over time, reinforcing his decision to surround himself with these stately plants. Cue his next project.

Barry Cox with one of his dogs, Scruff. Photo: Sally Tagg.

"I walked out my back door one day and thought, 'That space needs a church' – and so it began. I cleared the area in April 2011 and made the iron frame, drawing on all the research I had done over the years of studying churches. I wanted the roof and the walls to be distinctly different, to highlight the proportions, just like masonry churches," he says.

Alnus glutinosa 'Laciniata', or cut-leaf alder, was chosen for the roof. The variety is flexible enough to be trained over the temporary iron frame; in a few years the main branches of the alder will become the frame itself. It was important to have a sparsely foliaged deciduous type for the roof to allow the light in, especially in winter, otherwise it would be too dark for guests to see and the floor of grass would die.

The altar has special significance: it comes from Barry's family church in Shannon, and is made of marble from Lake Como in Italy, from where his ancestors hail.

The walls of the church are Leptospermum macrocarpum 'Copper Sheen', an Australian tea tree whose foliage is thick and textured, with a colour that resembles stone. To keep it looking lush, Barry trims it every six weeks.

Barry made all the wrought iron framework using metal from his workshop. Photo: Sally Tagg.

A 'Dublin Bay' rambling rose weaves its way around the top, chosen for the colour and romance it brings as well as for its long flowering season – the first blooms appear in October and it can still be in flower in June.

The church is set within a low border hedge of Camellia 'Black Tie', a dense hedging plant that requires little maintenance except for regular clipping. At the pathway entrance a pair of wrought iron gates, formerly on the Cox's family farm, set the tone for respectful behaviour – we are, after all, entering a church and its grounds.

Perfectly proportioned Acer platanoides 'Globosum' rise out of the camellia hedge and stand sentry either side of the gateway. These lollipop-like trees do not grow very tall and sport bushy tops that require a little pollarding to keep them looking uniform.

Across the walkway from the church a double-lined avenue of Betula utilis var. jacquemontii or Himalayan birch, with their snowy-white, lacquered bark, leads to a labyrinth, the design of which is based on the walls of the ancient city Jericho in 460BC. Lined with mondo grass, Barry has had to discourage pukekos from pulling up the freshly planted juveniles.

Barry officially opened the Tree Church and grounds to the public in January this year, having bowed to pressure from relatives, friends and local garden clubs. It wasn't his original plan – he just wanted to grow a Tree Church for his own enjoyment, and realise his study of ecclesiastical architecture – but when his nephew asked if he could get married in the church, Barry couldn't say no.

Barry owns a range of vintage gardening tools. Photo: Sally Tagg.

It wasn't long before more happy couples found their way to celebrate their nuptials in this one-of-a-kind venue. A friend and former colleague, Donna Signal from Cambridge, was delighted to get married in such an unusual, living green space.

"We wanted somewhere different and special, and the Tree Church is all of that and more," says Donna. "We are not religious at all, but felt that the Tree Church gave our wedding a sense of venerability in a natural, relaxed and non-denominational way," she adds.

The effort and time it takes to create even the most simple of structures by pleaching trees together is no mean feat. So you would be hard-pressed to find another structure in the world in the same league as the one Barry Cox has created in this corner of the Waikato. Some "cathedrals" have been formed in Italy and the UK by planting trees close together, but none have the structural complexity of Barry's Tree Church.

After a few local garden clubs had visited and been enthralled at Barry's sheer creativity and green engineering expertise, the formerly reluctant host was brought round to the idea by the gentle encouragement and rewarding feedback from fellow gardeners.

"I like that the gardener visitors enjoy and appreciate my Tree Church," he says. "I find that gardeners and those passionate about trees are generous people who simply want to share and enjoy with like-minded others. Visitors have said that they find the Tree Church relaxing and that their worries disappear. I find that sort of feedback immensely rewarding."

Barry Cox is not one to beat around the bush, if you'll pardon the pun. A spade is a tree spade in his view and he has been known to move trees three times until they're in exactly the right position.

He is also well aware of the amount of maintenance and upkeep that a garden and all the trees within it demand. "It takes me five hours to mow the lawns and at least three hours of final primping to get the gardens and Tree Church to the standard I need to be happy for an event," he says.

Zephyranthes candida blooms. Photo: Sally Tagg.

Weather can complicate matters. If the day before an event is windy or rainy, or both, it takes even longer to remove wind-blown leaves and adjust shifted foliage. But Barry is not deterred, and when I ask him about his long-term plan for the gardens he shows me a specimen jar containing bits of his elbow cartilage. "My joints are wearing out," he says matter-of-factly. "So I am developing a chainsaw and hedgecutter that will be more manageable, especially as they are used weekly throughout the summer."

In addition to the existing vegetable plot, bog gardens and cut flower patch, there are plans to complete the European garden behind the tree church, creating a sense of balance with the labyrinth. There is also a natural amphitheatre that Barry would like to plant out for outdoor summer events.

Barry is now in his mid-60s, but instead of looking ahead to retirement and downsizing to a postage stamp-sized lawn and potted colour like many former dairy farmers his age, he is formulating a plan for the future of the Tree Church and fashioning equipment accordingly.

It's this clever approach to adapting to changing circumstances and challenging that will stand him in good stead for years to come.

Visit treechurch.co.nz for more info.

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