"I define it as the elicit cultivation of someone else's land," Reynolds explains.
"It's gardening land that you don't own, you don't have permission to use. It's usually public land in a shabby condition."
Reynolds has become a pretty public figure, but he says it's hard to say how wide the concept has reached today, though he's pretty sure it's on the up.
"My focus is on encouraging people to just go and do it. They don't have to join me. But my sense is that it's increasingly popular because of traffic to the website and Facebook page."
This week Reynolds is heading to New Zealand for the first time, to try and spur some interest in the movement here. He isn't aware of any Kiwi creations - but he's keen to hear about them (another nudge to share your projects in the comment section below!)
He's also keen to inspire people to get a guerrilla garden growing.
His first tip: "It's about looking for a suitable space - neglected public spaces that are manageable."
And don't worry about flying solo with your idea. In fact, this can work best at first so you don't feel trodden down by naysayers, Reynolds says.
"Don't worry about getting a great group of people together. That's not in the spirit of it. Start small and allow the group to expand naturally. If you're the one with the idea, don't let other people's opinions hold you back.
"You'll be much more confident - fear is the biggest barrier."
* Richard Reynolds will be speaking at BizDojo, Co Space on K Rd, Auckland on Wednesday 3 April from 6 to 8pm. The event is free. Go here for more info.
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