"I just thought we should have a very simple system to teach people how to weave," she said.
One billion single-use coffee cups are thrown out in Australia each year, equalling more than 60,000 kilograms in waste.
By taking a discarded cup and cutting lines from the lips to the base, the cup makes the perfect frame to weave weeds into a bowl.
"It's a quick way of making a little vessel or basket using a coffee cup and a few natural materials," Ms Cantrill said.
"Making a few baskets isn't going to save the problem, but as long as it makes people think about what they are buying."
Ms Cantrill loves to reuse items that others see as waste.
From plastic bags and florist ribbons, to sticks and weeds in the garden, almost anything can be weaved into something new, she said.
"Once you know how to weave, you can use any materials."
"I tend to use natural materials, but people who live in cities are interested in using plastics and coffee cups and other sorts of recycled materials.
"I generally use iris or day lilies, watsonia — a lot of things that are considered weeds are very useful."
Weaving with weeds
Ms Cantrill said preparation was the key to transforming weeds into weaving fibres.
Once harvested, the weeds have to be dried by wrapping them in a towel and placed in storage.
"When you want to use it you have to take it out, dampen it down, wrap it up and condition it overnight and you are ready to go."
Ms Cantrill said with the right framing, the baskets could be made for any use, from pen holders to household items.
"The fact that you can create something from nothing is really exciting.