A Coromandel cliff-top garden
When award-winning landscape designer Bill Holden was invited to create a garden on a cliff face just north of Tairua in the Coromandel, he decided to go to sea – literally.
The owner had specified one main design goal for the garden: it had to blend seamlessly with the landscape and be as invisible as possible from any vantage point. So Bill brought his boat up from Rotorua, where he was living at the time, launched it from Tairua Harbour and sailed it up the coast until he could see the excavated site.
It wasn't hard to miss.
"There was a massive scar on the landscape, so immediately I knew my task was to make that scar disappear once the house was constructed." He took some photos, did a spot of fishing, then headed back home to get started.
He chose a palette of natives from genera that grow naturally in the coastal landscape: phormium (flaxes), muehlenbeckia, leptospermum, pseudopanax (five-finger) and coprosma. To create structure and provide terracing for stability he added rocks, lots and lots of rocks – 400 tonnes, in fact. It was important to Bill that the rock matched the walls of the house and was local, which would reduce the garden's carbon footprint. Not that this made it any easier; delivery and positioning rocks was definitely the biggest challenge of the job.
"It was the side of a cliff. Man, I did some hair-raising sweating. It was a nightmare, all through the winter of 2010." He admits they lost one or two off the side: "I'd hear crash, crash, crash down to the sea." Fortunately, the rocky shore below is inaccessible to the public. But now the rocks form a framework on this 2ha section.
Bill's rule for rock placement is that in order for them to appear natural, they must be planted in the ground one-third in, two-thirds out, so that in three or four years only about a quarter of the rock is visible as the garden grows up around it.
Five years on, boulders at the top of the gully overlooking the sea are submerged in pillowy mounds of Coprosma acerosa 'Hawera', which look bouncy enough to lie on.
The plant is a favourite of Bill's – and the wild rabbits. Karen Pinnington, the gardener who has been working on the property since day one, is encouraging the coprosma to grow into a carpet and says the secret to its bounciness is sheep manure and lots of blood and bone.
"Natives love the old blood and bone – nothing flash," says Bill.
Rock terracing was also critical for one of the earliest stages of the job, which was to come up with a solution for the gully leading down to the shore 44m below.
At that point, there was no track down to the sea but Bill told the owner that for his design to work he still needed to give the impression you could get down there.
So he created a path that zigzagged part way down the cliff and planted the gully with native flaxes Phormium tenax and Phormium cookianum, cabbage trees and the large-leaved kowhai, Sophora tetraptera, making it a five-star restaurant for visiting tui and kereru.
By now you may have gathered Bill is a bit of a rock man. His father was creating rock gardens using alpine plants back in the 1960s for farmers around Rotorua.
"I loved creating gardens with my dad," says Bill. "We also propagated alpine plants and would sell them."
Many of the southern alpine plants couldn't cope with Rotorua conditions but some, like the Marlborough rock daisy, have endured and are commonly planted there today.
Sadly, Bill's father never lived to see how his passion had passed on to his son, who has won many awards from the Landscaping Industries Association of New Zealand.
Bill is quick to credit Karen with a lot of the success of the Tairua garden; she spends around 14 hours a week there.
"Often you'll create a garden, then go back a few years later and feel disappointed that it hasn't been maintained. Karen has continued to help the garden evolve and I'm really happy with how it looks."
Karen, who looks after many of the large gardens in the area, has done the hard yards from the beginning, digging in 20 truckloads of mulch and planting out most of the property. As well as pruning and fertilising she replaces ailing plants with different ones – if they can't cope with the extreme coastal conditions, they're out.
Such was the fate of the renga renga lilies planted on a shaded clay slope, which Bill describes as a "hard basket" area. The famously fussy plants started dying so Karen has replaced them with Australian frangipani. Luckily, Bill isn't a purist and doesn't mind a few offshore plants intruding into his native scheme.
The shade-loving native groundcover Pratia angulata thrives in this tricky corner, even surviving the attentions of the resident quail.
One of the stalwarts here, which has provided stability from erosion and a microclimate for other plants, is the five-finger hybrid Pseudopanax lessonii 'Cyril Watson', named after a former employee at the New Plymouth-based nursery Duncan & Davies. It's one of Bill's favourites because "it grows in clay, is hardy, grows quite quickly and has pretty foliage with a nice layered texture to it".
But if a prize could be awarded for speed, it would go to the Pittosporum crassifolium, which Bill says is one of the fastest-growing native revegetation plants.
If developing a garden on a steep clifftop with hard clay wasn't challenge enough, the weather soon presented new problems.
In winter, heavy rain causes the hillside to leak, and natural springs to run through the property. These created a wonderful swimming pool for Karen's dogs but turned the site into a quagmire that was dangerous for operating machinery. The architect dealt with the problem by running one of the water courses under the house and down the cliff. He also suggested retaining the bank above the house with gabions in wire baskets.
"The owner wasn't sure," says Bill, "so I said, 'Why don't you turn them into natural water features using large rocks?'" It was a considerable investment and the owner took some convincing, but Bill drew up some plans and he agreed.
Today the watercourses have been tamed into waterfalls, one creating an oasis-like backdrop to the swimming pool and the other a living wall next to the kitchen. While the poolside waterfall has been beefed up with a tank and pump, the one beside the house runs on its own supply and Karen says the water thunders in heavy rain, sometimes overflowing onto the courtyard.
Watercress, which the owners pick and eat, grows amid its rocks alongside native Fuchsia procumbens, ponga and the palm-leaf fern Blechnum novae-zelandiae.
Despite the continual need for problem-solving, Bill says the garden is easily one of the best he has created. "My heart was always in it, but man, it was no cakewalk." But perhaps it's the most challenging projects that provide the most satisfying outcomes.
The March issue of New Zealand Gardener magazine is on sale now.
- NZ Gardener