"Tried growing mushrooms before, and it didn't work" – if I had money for every time someone has said that to me I'd be a very rich man...and probably no longer a mushroom farmer! Mushrooms are notoriously unreliable to grow, partly due to the mass-produced low quality kits that people often try. Almost mystical organisms, they seem to pop up in the wild in an unpredictable way, often only appearing for just 5 or 6 days before vanishing back into the ground again, not to be seen in the same spot for another year or three. Yet, despite a poor reputation amongst home growers, by using a particularly simple technique and getting a bit of insight into how mushrooms grow, it is possible to successfully grow your own gourmet mushrooms at home. So how exactly are mushrooms cultivated? How can you have success at home? And more to that point - what's all this got to do with waste coffee grounds?