Let me elucidate: I work in the hatchery part of our freshwater site and where I work we have 1 metre tanks containing 70,000 fish at half a gram each. To get them growing at their best at this stage they are getting 24 hour light so they can keep feeding.
When they get about a gram or more, they are put into 10 metre tanks where they grow under natural light cycle. This will be happening very soon, actually. They will be under the natural light cycle eventually and next spring when the days get longer they go to salt water.
If you want to put the fish in salt water in the fall for some reason, it can be done by covering the tank with a big tarp and putting lights underneath to make, for a good comparison, a growroom inside the greenhouse where all those tanks are. You give them short "days" over the summer by keeping the lights on for the appropriate time. Then you make the photoperiod progressively longer to simulate spring and the fish go out to the bay without a hitch when their "days" are the same length as the natural ones. So you see why it would be interesting to try the same thing with a plant.
I know it's a little late to start it now, but in the early months of next year we'll have to start one. Like a 12/12 from seed at first and whatever monstercrops out of it after a first harvest.