Gardeners are no strangers to the concept of weeds – it might be a clump of bindi-eye that pop up in your lawn, oxalis between your pavers or an errant dandelion in your flower beds. And while these may be annoying, and a little inconvenient, they are often the only obvious exposure home gardeners have to an invasive plant. But the reality of weeds in Australia goes far beyond the fence line – in fact, 70% of Australia’s most damaging environmental and agricultural weeds have their origins as garden plants. The importance of knowing what we grow, and how it may impact the wider environment is something that all gardeners should have an understanding of.