1.Make the shop's prices lower.Common plants go for 8 bucks,and I'm expected to get 800 to be able to experiment with crossbreeds(Level 2 soil).What doesn't help is your coustomers are braindead.They are staring right at a plant and don't know the giant plant is there.It's understandable in Fish tycoon,I myself can barley see the things,but bright plants?On the subject of coustomers,there is a coustmer possibility that looks a lot like Mario.Hope you got a good lawyer.
2.Take off the "Doses" system on level 1 items.If you're going to put a price of a hard earned 85 bucks just so a plant can('t) see the light of day with insect poison means that likley another one is infested.And another.You're going to have at least the whole bottle down in 3 hours.But now you're broke,and the most expensive plant is dead.
Why not make it so that you can get refills at lower prices?
Speaking of spray,the "Use _bug_ spray" arrow in the tutorial points to plant food.Took me the whole bottle to find out it was a seperate item.