Plant 10 chilli seeds as close as you can in a circle.

If you get them close enough you only need 4 sprinkles of red fertilizer.

Then sell them for 400 each and use less money to grow them again. Can do 10 at a time in the store or till you run out of room from you seed bag.

Repeat this process with the rose seed and red fertilizer when you get it an d you'll get ( when fully grown) $1400 .

Repeat this with the orcid and the "special mix fertilizer" when you get it and it will be worth $1800.

This pretty much works on all fruits and veggies and plants but make sure you use the right fretilizer, blue with blue, green with green, etc, and if it makes the weird noise then you need to use the "special mix" bag.