There is the planting bed next to the hacienda. You clearly should grow something there.
Beans! The small portal gets you to the lab. Grab the beans.
Now, open it.
Isn't it quite obvious you have to sow the bean, then?
Disappointing. You don't have the time to wait for the bean to grow. If you just would've sowed the bean years ago.
Remember where one of the students ended up? As a hillbilly living in the hacienda.
He is just falling through the portal in the lab floor. He will end up in the sowing bed and take control of the hacienda.
Okay okay. Go through the small portal and throw the bean into the portal (frozen strudel).
Behold, there's the beanstalk!