Balwyn Paul Birch curator at Maranoa Gardens.

Co-curator Paul Birch tends to a wattle. Photo: Rodger Cummins

A SEAT in Maranoa Gardens is dedicated to a deceased elderly couple who visited the site regularly and found ''peace and comfort'' in the tranquil surrounds.

One can understand why. The native garden, tucked away in the backstreets of Balwyn, is a hidden botanic gem. Registered with the National Trust as a site of state cultural significance, and run by the City of Boroondara, it is one of the few public gardens devoted to Australian plants. Right now it is testament to an early spring with the first of the wattles - there are 140 species in the gardens - a study in patriotic green and gold.

A stunning hakea displays its red poker-type flowers, while Grevillea 'Superb' is a haven for birds. Co-curator of the 111-year-old gardens Andrea Dennis says the wattles will flower for another month along with the grevilleas, hoveas and correas, providing banks of colour.

Correa flowering at Maranoa Gardens.

Correa flowers in Maranoa Gardens. Photo: Rodger Cummins

This weekend Maranoa is holding its fourth annual festival with guided walks, tours of the acacia collection, displays by the Australian Plant Society, entertainment and refreshments. In past years there have been plant sales but due to myrtle rust, a serious fungal disease found in Victoria and affecting species of the Myrtaceae plant family, Dennis and co-curator Paul Birch have decided to exclude them this year.

''We don't have myrtle rust in the gardens but someone could come in with a plant to sell that may have been affected so it's not worth the risk,'' Birch says.

Entertainment will be provided by the Connies, a troupe of former tram conductors, performers, educators, ecologists and nature lovers, who will highlight Boroondara's recent Sustainable City of the Year prize awarded by Keep Australia Beautiful for its backyard biodiversity program, which among other things encourages residents to allow a continuous wildlife corridor through their properties.

Dig it.

There are more than 550 trees in the gardens, including 200-year-old red gums and wonderful older specimens such as a Queensland fire wheel tree (Stenocarpus sinuatus) and a smooth-barked apple (Angophora costata). The gardens are divided into a central arboretum and lawn, a dry area for hardy shrubs and plants, a temperate woodland and heathland, and a rainforest section. There are collections of grevilleas and banksia and flowering shrubs such as correas, croweas and acacias including A. cognata 'Limelight', which is planted near the entrance around the variegated brush box Lophostemon confertus 'Variegatus'.

The highest point in metropolitan Melbourne after the Dandenongs, Maranoa is the result of a purchase in 1901, by John Watson, of 1.4 hectares to develop a private garden using Australian and New Zealand plants. This was a rarity at the turn of the century, when the emphasis was on European trees, exotic plantings and Victorian or Edwardian landscapes.

In 1922, it was bought by the former Camberwell Council and opened to the public in 1926 as a botanic garden. In 1962, land was acquired from the adjoining Beckett Park to build a rockery, which was extended 25 years later to accommodate plants considered difficult to grow in Melbourne.

When I visited the gardens four years ago, the effect of the drought was obvious, with many plants under stress. Today it's a different story thanks to bountiful rains that have worked their magic, transforming the 2.6-hectare site into a lush treasure. ''There has been lots of new growth, which is wonderful, but we've also planted a lot over the years and everything's come up really well,'' Birch says.

Dennis says some plants have responded well to the increased rainfall during the past two years but others have not.

''Some have turned up their toes,'' she says. ''They survived the drought but all the rain was the nail in the coffin. We've lost a lot of old plants such as correas, as have many gardens.

''What is surprising is that a lot of old rainforest plants that you would think would need more moisture survived beautifully in the drought, such as the Queensland bottle tree (Brachychiton rupestris), but putting in new ones is where we had problems.''

While the oldest trees in the gardens are the indigenous red gums, the firewheel tree is thought to be more than 100. ''We've got records from the 1920s of plants that went in and there is a historic reference from 1910 from a person, then a child, who was given the first flowers from the firewheel tree by John Watson,'' Dennis says.

Over the years the council removed all the New Zealand species except for one tree, a kowhai (Sophora tetraptera), to create a unique Australian public garden, now a valuable resource for plant collectors, students and botanical enthusiasts, and a tranquil place for visitors. Just like the couple to whom the seat is dedicated.

■Maranoa Gardens festival will be held today, 10am-3pm, Yarrbat Avenue (off Parring Road), Balwyn.