Anyone looking at Glasgow's Centre for Contemporary Arts in Sauchiehall Street in recent years would have been wearing rose-tinted spectacles to conclude that everything in the garden was lovely.

As long ago as the Lottery- funded remodelling of the premises by architects Page and Park, the former Third Eye Centre has seemed to throb with artistic life only sporadically. Despite the inclusion of a custom-built auditorium and small cinema in addition to its gallery spaces in its expanded facilities, there seemed to be a vacuum at the heart of the building.

Controversially, the premises still belong to the Scottish Arts Council, although other institutions, notably the neighbouring Glasgow School of Art, have made overtures about acquiring them. Key to the CCA remaining in existence has been the requirement of the Lottery spend that it remains a public building. Often it has seemed a much less public one than it once was, however.

It provides accommodation (specifically office space) to other arts and arts-related organisations (The List magazine, Independance and Theatre Cryptic, for example, operate from within its portals), but that is hardly a public facility. Its shopfront face onto Sauchiehall Street is not a welcoming one (its cafe is hidden from view and its bar is up the hill on Scott Street) and there are restrictions on what can be done to open it out, because it is an Alexander "Greek" Thomson listed building.

Just as importantly, other places in the city have appeared to take over much of what the old Third Eye Centre used to do. Both Tramway and, ever increasingly, the Arches, are the city's homes for performance and live art. Tramway also shows much of the visual art that might previously have found a place nowhere else, and Glasgow has a city centre Gallery of Modern Art. There are also now more small concert venues than ever before in the city (even if a regular home for jazz, which the Third Eye used to provide, is still mysteriously missing).

Perhaps it is no surprise then that the CCA has been looking beyond its front door to new areas of activity.

Francis McKee, the CCA's artistic director, acknowledges that the Third Eye Centre had a broader audience and that the CCA has been too isolated. Part of the strategy to reach the people of Glasgow has been to go gardening. Beginning, perhaps appropriately, in the abandoned offices of Cultural Enterprise on the building first floor, seeds were planted. Big south-facing windows helped nature them and plants grew. Some people took the CCA seedlings away - vegetables, flowers and other plants - while others added to the herbaceous collection.

Staff become involved in the "guerilla gardening" scene in Glasgow, where unloved public spaces are invaded by unlicensed amateur horticulturists, determined to introduce a bit of natural colour, sustaining greenery and homegrown produce into the community. Schools working with the Healthy Living initiative in Drumchapel were fastest to respond to the opportunity to come on board with the CCA's outreach work, and spades, bulbs and trees made their way from that first floor office greenhouse into the hands of young people for whom many such projects might easily have appeared a little too worthy. In parallel, the CCA has been hosting cooking and gardening classes and leading foraging expeditions in the city.

The guerilla gardeners in Glasgow are also very busy on the other side of the city - notably in huge bulb-planting project at Townhead - and the CCA has also just acquired two large allotments off London Road in the East End (ones that are too large for a single householder to maintain, one actually including some woodland) to further its gardening ambitions. It's all very admirable, but is it art?

The answer is self-evident to McKee; the work is only reflecting a growing interest in such work among artists. He points out that in Ian Hamilton Finlay's Little Sparta in the Pentlands and Charles Jencks's Garden of Cosmic Speculation at Portrack near Dumfries, Scotland has two art gardens of global significance. Landscape and psycho-geography are critical to the practice of many artists in Scotland (Toby Paterson and Drew Mulholland being two immediate and contrasting examples) and ecology and the environment were central to much of the work at the degree show this year at Glasgow School of Art degree show, where the environmental art department established by David Harding has produced some of Scotland's most famous contemporary artists.

McKee rhymes off a huge list of individual artists in England, America and Scandinavia whose work chimes with the outreach work that the CCA has begun.

The exhibition programme in the Sauchiehall Street building is also closely linked to these concerns. The current show, This Land is Your Land, features films and video by Mark Boulos, Ursula Biemann and Bouchra Khalili and landscapes from the continent of Africa to the futures trading floor of the Chicago Mercantile Exchange, where green shoots are more scarce.

Of course, all this encouragement of fertility is emblematic of what McKee sees happening at the CCA. After much speculation about its future, the centre has stable funding, a new board and a new management structure with Bec Carey-Greive as general manager, leaving McKee to oversee the artistic side of business, in which he is assisted by three other programmers. There is also now an expectation that the building's cultural tenants will be involved in the public activity in the building as part of their rent. "We are a very small team," says McKee, "and we need their participation as well as their money. Theatre Cryptic's Cryptic Nights of new work in various artforms are part of this process, but organisations from beyond the building have also become regular users of it. Monthly Gaelic language club Ceol's Craic now has an established place and Americana club Fallen Angels is a newer user. The small cinema has hosted the Magic Lantern club for some time, and Camcorder Guerillas and the Jewish Film Festival are regulars too.

"We give away the space and help organisations to make use of it themselves, providing technical support while they do their own front of house. The space upstairs has become particularly popular with noise' bands."

McKee says the CCA is now supporting 30 to 40 other organisations through its open door policy and the different audiences they attract are cross-fertilising, virtually via their websites as well as by word of mouth.

He concedes that the CCA's role in recent years as a creative laboratory for the arts was often hidden. "We were too precious about it before and are now making the building work for the public. I think we have a broader spectrum of organisations and programme here than anywhere else."

For the time being that job as an umbrella for other organisations has the financial support of the city and the arts council but McKee concedes "there is a mystery coming up and it is Creative Scotland".

One of the partners he will be able to boast of there is the University of the West of Scotland. The CCA is providing for the students' work in music, drama and screenwriting and there is a link to the creative industries that entwines with the way the new body is supposed to see the arts developing. This Land is Your Land runs to July 25.