This weekend, the picturesque property will be given over to artistic endeavour as its sweeping lawns are made even more dramatic by 135 sculptures being put in place for a special fund-raising event.

All the sculptures are for sale, with a portion of proceeds to benefit Boundless Canberra, the all-abilities facility planned for the banks of Lake Burley Griffin. The Kids Cancer Centre and Smiths Road Rural Fire Service will also benefit from the weekend.

Organised by Open Gardens Australia and 666 ABC Canberra and supported by the Centenary of Canberra, the inaugural Sculpture in the Garden exhibition will showcase the work of 28 artists on the property on the Murrumbidgee River.

Canberra landscape architect Neil Hobbs curated the exhibition, saying the gardens provided a natural gallery for the work, with the sculptures easily spread out on the lawns underneath mature trees.

''There's a loose Canberra connection to all the artists,'' he said. ''They either trained here or live here or are from the region.''

The event is made possible by the generosity of the Gullett family, who have owned Lambrigg since 1949 and who also hosted Open Gardens Australia's big plant fair in 2010. Kate Gullett, who with husband Pete has lived on the property since 1987, said a big public opening always made them really tackle that never-ending to-do list in the garden. ''The reward is sharing Lambrigg with others, which makes it all worthwhile for us,'' she said. ''We're delighted that Open Gardens Australia think Lambrigg is worth opening. The gardens lend itself to this fabulous sculpture. It's going to look very bare here when they're all gone.''

Mrs Gullett said Lambrigg, whose homestead was developed by the Farrers between 1890 and 1894, was a special place to live. ''It's a labour of love,'' she said. ''It's a dear old house and a beautiful environment to live in. We've raised four children here and it's been a magic place for them to grow up in. It is work but it is rewarding.''

Centenary of Canberra creative director Robyn Archer previewed the event on Thursday night with Open Gardens Australia president Tamie Fraser.

Ms Archer said she had been looking forward to the exhibition for months.

''To offer mainly local sculptors a chance to show their work in this setting is the kind of philanthropic act that gives all artists opportunity and hope,'' she said.

''Given the number of ANU School of Art graduates involved, it's also another chance to acknowledge, in the centenary year, the huge contribution the school has made to Canberra and the region: the inclusion of big names in sculpture, such as Michael Le Grand, Geoff Farquhar-Still and Dan Stewart-Moore has ensured real quality to his exhibition. I anticipate nothing but pleasure.''

■ Sculpture in the Garden is at Lambrigg, Tharwa, on Saturday and Sunday from 10am to 4.30pm. Entry is $15 a person. No charge for children under 18. To get there, go to Point Hut Crossing, follow Point Hut Road to the T-intersection, turn left into Tidbinbilla Road towards Tharwa, and the garden is a further two kilometres.