How many plants are needed to keep someone alive?

[factotum]

A minor point of order though for the bamboo, it's 143 cubic metres per person not square metres. While on a planet you can generally ignore height for growing crops, this is not an option in a spacecraft or other fully enclosed environment.
While there's lots of 'empty' space underneath the foliage, it needs to be clear so that the plant can grow freely to absorb as much sunlight as possible (probably a giant park to help the astronaut's psychological wellbeing).

We're talking space station here, so there's going to be plenty enough headroom for the bamboo to reach its maximum height.