Phil Bishop, the general manager of merchandise at Bunnings Australia, said the company stocked a range of herbicides “for customers who prefer non-glyphosate-based products”.
But there are other approaches. Penny Pyett from the Permaculture Sydney Institute recommends getting to know your weeds.
“Can it be used for eating? Or feeding your animals, or medical? Because a lot of weeds actually have good properties,” Ms Pyett said. For example, chickweed is nutritious in a garden salad, while stinging nettles can be used as leafy greens – they don’t sting once cooked.
“Once you understand them, they’re not necessarily seen as a problem,” she said.
But if they are, there are plenty of ways to get rid of them without chemicals.
“Sometimes we use steam or boiling water,” Ms Pyett said. “We also use vinegar. It depends where it is, but in a home garden people can often just hand remove it.”
Michael Zagoridis, the farm manager Pocket City Farms in Camperdown, a 1200-square-metre site on a former bowling green, said hand weeding and “weed matting” were two options for a non-chemical approach.
Mr Zagoridis said he understood why Roundup was popular especially for large-scale producers concerned about crop viability. Yet chemical weed killers could have “quite serious consequences” for soil health, killing microbes and fungi in the soil that link to the nutrients in the plants.
“As much as you can just pump in fertiliser, you’re kind of just digging a hole for future generations who are going to grow food on that soil,” he said.
One alternative is weed matting – where a layer of film is put over the soil, and holes are made specifically to plant crops. Without access to light, the weeds don’t grow. The mat can be made of biodegradable material and composted afterwards, Mr Zagoridis said.
While Roundup is a herbicide, many gardeners would like to ditch insecticide too. One option is harnessing beneficial insects to eat pest insects – or as Bugs for Bugs director Dan Papacek puts it, “breed good bugs to take care of the bad bugs”.
Gardeners can attract “good bugs” by planting specific plants and by letting vegetables and herbs go to seed, according to online gardening advice.
Green thumbs can also buy beneficial insects directly from Bugs for Bugs in central Queensland, which has been running for more than 35 years. The company breeds 12 different types of insect, as well as traps and lures.
“Chemicals often have negative side-effects,” Mr Papacek said.
“A lot of insects are very capable of developing resistance – they sort of learn to out-smart the pesticides, if you like. If you use them too much, they become ineffective.”
Matt Bungard is a journalist at The Sydney Morning Herald.