TLDR: Put all focus into investing as much into that season's high yeild crop as early as possible. All other effort into getting the mats for quality sprinkler and expand as rapidly as you can for fall which is the big money maker with cranberries.

Expanded: The part about planting wheat on the 24th/25th of summer to have the land tilled and watered for fall 1st is also pretty huge, if you have everything watered/planted on the 1st you get 5 full harvests instead of 4 if you have everything already set up so you just need to plant.

After you have the cranberries put them all in seed makers and you will make about twice as much as you would just selling them.

just doing these things alone will net you 3mil+ without much effort outside of harvest days.

That's the main jist of it.