Gardening: Family garden of Eden

A broad stone staircase blends splendidly with the Mt Eden landscape. Photo / Meg Liptrot

Artistic heritage brought to fruition in this volcanic environment.

The Heroic Garden Festival, now in its 19th year, offers the chance to visit 26 gorgeous Auckland gardens, and all for a worthy cause - fundraising for Mercy Hospice Auckland and Hospice North Shore.

Among this year's highlights are two special Mt Eden gardens belonging to an artistic family, one of these the garden belonging to Ben Hanly and partner Suzanne Johnson. The couple are first and foremost stained-glass artists. A tall A-frame studio in their garden was custom-built to house Holy Trinity Cathedral's stained-glass windows, which they created. The cathedral's Great Window, designed by artist Nigel Brown, is said to be the largest expanse of stained-glass in the Southern Hemisphere.

The couple have just finished working on a commission for Peter Jackson and have collaborated with many artists in the past, including Ben's late father, the great figurative painter Pat Hanly. Lucky Heroic Garden Festival ticket-holders will get a peek at their studio while visiting the garden.

With Johnson's design eye and Hanly's horticultural training, they have built a garden set to dazzle. Scoria terraces define the structure of the garden, with a broad stone staircase rising from street level to a well-tended lawn. Johnson was inspired by gardens of the French Riviera, with their elevated sites, stone terracing and olives, a natural fit for the abundant scoria and slopes of volcanic Mt Eden. The lower garden is sun-baked, and drought-tolerant plants circle a small informal fishpond.

Ben Hanly and Suzanne Johnson's stained-glass studio. Photo / Meg Liptrot

The upper courtyard was levelled during the building of their glass studio, and is the official visitor and client entrance.

This stunning space is a more formal courtyard garden with potted topiary, cycads, vireyas, twin persimmon trees and a sculptural Dracaena draco tree framed with mature box hedging.

A rectangular pond with blooming waterlilies provides a contemplative space to while away the time.

One of Johnson's favourite plants in the courtyard is a large Dendrobium orchid, which she is patiently waiting to see flower.

They have an arsenal ready for dealing with snails this year, after discovering by torchlight a horde of snails demolishing last year's flower buds.

Californian tree poppies and delicate true geraniums, another of Suzanne's favourites, daintily bloom around the upper lawn. Here, bearded irises are gorgeous in spring, she says. Near the kitchen they have raised vege and herb beds in a boxed, circular design.

Keeping a show garden in peak condition

Hanly is protective of his immaculate lawns in anticipation of the garden festival, and while we talk he makes an effort to stand on the paved edging. Without being asked, I comply. Garden festivals put a strain on garden owners as gardens need to be tended to perfection.

Keeping on top of watering is a challenge, as volcanic soil with a substrate of lava rock is exceptionally free-draining. Irrigation water flows from the garden through the scoria into lava flow aquifers, so their water, Hanly points out, ultimately ends up in Western Springs. Despite this, the special qualities of this volcanic area allows Mt Eden gardeners to grow the type of plants those with clay soils can only dream of.

The couple keep their exotic specimens happy with an application of slow-release fertiliser every three months, and Johnson tends to any lacklustre specimens by hand-watering with liquid fertiliser.

Hanly says they held off using Rooster Booster manure until I had gone, as it's pretty potent.

I wondered how on earth they have time to work on their glass masterpieces when they maintain a garden that looks like it wouldn't be out of place at the Botanic Gardens.

The couple will open their garden again for the Heroic Festival, because they've had a bit of involvement with Mercy Hospice over the years. Johnson has previously donated her design time for the stained-glass windows behind the hospice's reception

heroicgardens.org.nz

• Next week: Gil Hanly's Mt Eden Paradise.