The best recommendation for this is to plant some seeds that take 3 days (or so) in a 1/3 of your farm, some seeds that take 2 days in another 1/3 and finally peppers or soybeans in the final section (Yes, the ones that take a day!). This way, when the peppers ripen – you can plant more. The next day when the level 2 Items ripen (Just before the newly replaced crops that take 1 day) you can harvest both of them, and plant twice as many peppers/peas. And on the final day you harvest the entire farm. This leads to good reaping of Exp and a good amount of money from all the harvesting.

Planting an entire farm of 1 seed can become tedious when getting to the harvest. With relation to the previous paragraph – you could stagger the harvesting/plough/planting. With 2 crops that take 2 days to ripen. Plant them on alternating days so you only ever have to harvest half the farm at once. This way also ensures you get a stead stream of money everyday in case you do spend it on extra Exp like buildings, trees Etc.