The seeds are a start, but we need this lemon to grow - quickly.
Through some crazy chemistry!
Refer to the lab notes again to see if there's a page that can help us out.
On the second-to-last page, the researcher notes plants in the botany lab growing extremely large when the following things are combined:
The botany lab may hold some clues.
Apparently, the Erlenmeyer flask is full of 'Substance X', so we just need to find Substance F and an oily additive.
We don't know much about it, but have to assume it's under lock and key - check the various locked cupboards around the base.
More specifically, look in places where it would be rather inappropriate to store strange substances.
There's a suspicious-looking locker in the detention cells area; examine it, or check the signpost for the boys' quote.
Use the security card we got upstairs on the locker to bust it open, and get a small key for our troubles.
You can use this small key to open a cabinet in the botany lab, granting access to Substance F.
You may have found one already - if not, check the more technology-focused rooms.
Sometimes hardware just needs oiling up, you know?
Return to the server room, where you can find sesame oil sitting out in the open.
Follow these hints if the guard is being a bother.
We have everything we need - put the lemon seed, sesame oil, and substance F into the Erlenmeyer flask, then enjoy the show.