Is this a gardener’s best summer friend?

Not only have the two tillandsias perched on the very top of Eureka Tower not been given any care all summer, they were not given any attention for the five summers before that. They have powered on through blistering heat, unrelenting dryness and occasional 200km/h winds with just the water that falls from the sky.

Last time owner Lloyd Godman cared to look at these experimental specimens, his Tillandsia bergeri had 13 new growing stems while his Tillandsia ‘Houston’ was so big it was poking out of its soil-free cage.

Lloyd Godman with some of his air plants, or tillandsias, in St Andrews.Credit:Justin McManus

They look as lean and dogged as you would expect of plants that survive on nothing but air and a lick of rain but Godman is a huge fan of their silvery glow and vivid flowers. He has big plans for these can-do species.

If they can clamber across open rock faces in their native South America, he sees no reason why they can’t grow over steel and concrete buildings in Melbourne. Since 2014 he has been testing their mettle in the most difficult spots he can conjure.

Some of the tillandsias in Lloyd Godman’s glasshouseCredit:Justin McManus

The Eureka roof, which sits more than 295 metres off the ground, is just one place. They are also under eaves, above sewerage vents, on walls in rain shadows, in dimly lit landings and all sorts of other unlikely, unforgiving spaces all over town. He has lost a few (“if stuff doesn’t die, you’re not properly testing it”) but nothing like what you might expect of plants placed in empty wire cages and all but ignored.

Eighteen months ago Godman joined forces with another bromeliad devotee (they met at the Bromeliad Society of Victoria), Geoff Beech, and together they are working out just how far they can push a tillandsia.

In their respective gardens the two are also busily building up tillandsia stocks with the aim of deploying them en masse on buildings. Godman says while tillandsias help reduce heat and combat pollution “without the cost and complexity” of other roof gardens and green walls, it takes a lot of tillandsias to provide a dense-enough cover.

Tillandsias growing in Lloyd Godman’s glasshouseCredit:Justin McManus

Godman has thousands of them – made up of about 300 different species – literally hanging around his St Andrews garden. As well as propagating them by division, for the past seven years he has been hand-pollinating them and raising them from seed. He sows the seeds, which look as fluffy as fairy floss, on mosquito net that he keeps at 22°C in his glasshouse and mists with water daily. He has about 10,000 such seedlings. But they are slow-growing and even after about three years are only a few centimetres long.

Being CAM photosynthesisers, these plants collect their carbon dioxide at night instead of in sunlight like most plants. This means the plant’s leaf stomata are closed during the day, reducing the loss of water through evapotranspiration and helping them to survive in arid environments.

Godman says he has found that only those tillandsias kept in places that rain never reaches need to be irrigated or, given they absorb water through their leaves, “misted”.

“What we want to prove is that these plants are self-sustaining,” he says. “You can put them in and walk away for five years and do nothing. They take no maintenance, have no weight and [mostly] don't require water.” Godman says he and Beech see the potential of lightweight, tillandsia-covered screens that can move across windows and skylights “like curtains” providing sun protection when it is required.

Godman, a New Zealand-born artist  who has lived in Australia since 2005, has been growing tillandsias on frames for more than a decade. In 2009, his tillandsia installations were suspended in Melbourne streets as an example of “super sustainability”. Before that he was making “photographic” images on neoregelias, also in the bromeliad family, by applying shapes cut out of tape onto the light-sensitive foliage and leaving it for four months.

But Godman says the “urgency of climate change” has prompted him to give up his “traditional arts practice” and to look at different ways to bring plants into cities and “cool them down”. He has found that one of the barriers to growing tillandsias as a cooling device has been that they don't look particularly lush and cooling.

“People do like plants with big green leaves but if you have a solid rock face that is being beat up in the sun, which is what a building is, you don't find big-leafed plants growing on top, you find different things altogether,” Godman says. “You find these.”

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