Plant sprouting like all processes of work requires energy. The energy comes stored in the seed which has a bit of fat (oil) which helps the seed to grow to the surface at which point it starts photosynthesizing light which allows it to grow into a large mature plant.
This is a great metaphor for the oil age. We exploited energy from coal, oil, natural gas, which was simply trapped under ground and created initially by photosynthesis millions of years ago. Whereas at some point that bit of cheap no-work-to-get energy goes away and we really need to start making our own.
-- Great metaphor, crappy point, worse post.