Every week, Allan Hoppe and Ryan Cuthbert visit a community nursery to pick vegetables.
They push through a dense tangle of fronds and come out with red, orange and yellow tomatoes, plump zucchinis, cobs of corn and pumpkins as big as footballs.
This week they even worked together to identify the best veggies, leave the ones that needed to be left to ripen, and avoid a bearded dragon who sat on a vine, silently watching.
"I think we should leave it alone," Mr Hoppe said.
"It's already made its home, its habitat.
"If this is its habitat, we can't interfere with it."
For the two men, their weekly garden visits are a kind of therapy, a way of learning by using their senses of smell, taste and touch.
That is a topic about which Ben McCallum is passionate.
"Some people say we should prune things back and get (the garden) looking a bit more orderly, but the idea is when you walk through it the plants are touching you, and it stimulates brain development," he said.
"Say you're brushing past a pumpkin or a cucumber with spikes on it, it might prick you, you say 'ooh', but it's developing a part of the brain you don't develop unless you're touching things.
"Coriander and fennel seeds, we let them set on the plant; when you walk through they touch you and release these smells.
"It's all about stimulating synapses in the brain."
He said spending time outside had a calming effect.
"We have a natural proclivity for being with plants," he said.
"In cities people become quite detached from that.
"Even in regional towns, the advent of TV has meant people losing opportunities to use their senses because they're spending most of their time indoors."
The vegetables the men harvest are put in a grow free cart out the front of the nursery on Greenlands Drive for anyone to take, or shared among the staff and volunteers from the Eastern Hills and Murray Plains Catchment Group who run the nursery.
We have a natural proclivity for being with plants. People become quite detached from that.Ben McCallum
They also complete a different task every week – this week, for instance, they were encouraged to find species which smelled like lemon.
Therapeutic gardening, he called it, or sensory modulation.
In time, he hoped the catchment group could secure a source of funding and offer it to more visitors.