Trott’s Garden is on a scale rarely seen in New Zealand, covering more than 2.8ha of a 4ha site and including dramatic 110m herbaceous borders, and large and intricate knot gardens. Trott and wife Catherine lived on the property for 37 years.

“We started it from a bare paddock,” he says. “But it wasn’t a wrench to leave. I was worried I would start to tread water there if I stayed. And I wanted to start a new garden before I got too old.”

So late in 2017, Trott’s Garden was taken over by a charitable trust (it remains open to the general public), and the couple downsized to their new property, a 1920s villa near Ashburton’s town centre.

Well I say downsized, but the new garden is still 2500 square metres (about half an acre in old money) which would be considered a large urban garden by most modern standards. “I thought I couldn’t handle anything smaller,” Trott says. “And we’re lucky because a lot of the sections around here are just 800sqm.”

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Many people of a certain age and stage moving on to a smaller property are also looking to create a garden that demands a little less of their time and energy. But Trott says his aim was never to make a low maintenance garden here.

“I mean the size of it means it’s a thousand times less work. But actually I created elements from the big garden on a smaller scale. Some people were surprised by that but it doesn’t worry me what people think.

“When making a garden, you should make it how you want. People always say the work in the garden must never be finished. But I always say neither is housework.”

In front of the house here is a collection of different topiary shapes. Large and elaborate, they were planted just five years ago but Trott had actually been growing them on in pots for 20 years by then.

“I had been growing them in the nursery,” he explains. “I thought they’d be a good retirement fund. But then buxus blight hit New Zealand. So I thought what will we do with them. Catherine had the idea we should plant them out the front.”

Alan Trott created a garden of international renown, then he downsized ... ish

He was influenced, he admits, by the French garden, Jardins de Sericourt, which has a famous walkway passing through box clipped into cones and spirals and balls, every one different. “That really appealed to me,” he says. “And it worked with the pathway we had here.”

Move to the back of the garden and you find a hot border where red, yellow and orange dominate. That should not surprise anyone who knows anything of Trott’s gardening history – the Red Garden is a signature feature at Trott’s Garden, and he won gold at Ellerslie Flower Show in 2009 for the garden I See Red made in conjunction with Sir Miles Warren, creator of Ohinetahi in Governors Bay; Marilyn McRae, then head gardener at Ohinetahi; and Pauline and John Trengrove, Sir Miles’ sister and brother-in-law.

“I like red,” Trott says. “I like hot colours. But at the front I have focused on plants that flower in blue, white and pink. By doing that you can grow a variety of plants. Whereas if you focus on just one colour, you limit what you can grow.”

The smaller size of the garden does mean he has to be more conscious of his choices, he says, especially when it comes to large structural trees and shrubs.

“It’s important in a smaller garden to be very selective in what you plant,” he says. “So I only grow named varieties. I only buy things that have been proven as quite spectacular. I haven’t got room or time for plants that don’t perform. Life is short and the space in the garden is short. I only want the best of the best.”

And for maximum impact in a smaller space, Trott says, you cannot beat perennials. “Perennials went out of fashion for a while because people said they were a lot of work,” he says. “That’s absolute rubbish. They come up like clockwork in spring. Many of them have amazing foliage which lasts right until the first frost, when you cut them down. Almost all of them are hardy. And they make an absolutely awesome garden, provided you are very selective in which you plant.”

He uses a lot of grasses too, which he leaves all through the winter for structure and foliage and cuts down at the start of spring. “So they keep the garden going over that period.”

When they moved onto the new property, he and Catherine made the decision not to open this garden to the public. “We want to have the garden to ourselves,” he says. “So we are out of public life.”

That doesn’t mean he’s spending any less time in the garden though. “It’s my hobby and my passion,” he says.

“So I don’t really count the time. I’m always out in the garden. At this time of year I carry a notebook so I can make notes of what I want to change. What’s going to go, what’s going to get shifted, or discarded. A garden is not an object but a process. It changes. And you change your ideas too.”

He’s been experimenting with lush foliage plants, including some such as bananas and brugmansias, that are marginal through Ashburton winters, “although we are not getting the length of winters that we used to, and the frosts are not as hard”. But also, he says, he has more time to fuss over plants now. “I put them in my glasshouse over winter. And I can wrap them, which is not a big job.

“There’s always something new to try,” he says. “There’s always plant families you can experiment with that reward your interest. I actually don’t know how I got so interested in plants if I am honest. But I always have found them fascinating. I still do. Watching them grow from a seed, from almost nothing. Watching them change daily. I’m pretty lucky. It keeps me happy, it keeps me busy. And I have plenty more I still want to do.”