Although I tend to resist the use of marketing lingo, there is a word and concept that may be critical to your success in farming in Island of Happiness. That word is 'planogram'.
I never heard of it until some one who worked in retail told me about it. A planogram is a map or drawing that displays the precise placement of every item sold in the shop. It is used primarily by sales reps to see how much space their rivals are being given as well as making certain that products they wish to feature are being given the most visible placement.
In Island of Happiness, I have come to the conclusion that a Farming Planogram may be essential to your success or failure with respect to Crops both in your Field and in your Greenhouse.
There are two considerations that rule Crop growth in IoH: Sunlight and Water. As discussed both in my Guides and on this site, there are Crops that actually need LESS water to survive. These Crops will die if you overwater them.
Furthermore, slow-growing crops will remain nothing more than seeds for weeks sometimes, a situation that may confuse you if you forget where you planted individual Crops.
You need to be familiar with the physical appearance of every Crop at every stage of growth. I have tried to post screenshots of the various Grains here to help players but it is not only Grains that require identification. A Crop like Yams is a Crop that can be overwatered easily and if that occurs, it will wither in the Field. Knowing where you have planted your Yams, therefore, becomes critical when you water your Crops.
My suggestion therefore is to divide both your Field and Greenhouse into halves or quarters, allocating one side or quarter to Crops that thrive on Water and a different side or quarter for those that require very little water. If you divide your Field and Greenhouse into quarters, you can make a further division between fast-growing Crops and slow-growing Crops. This would be far less labour-intensive than writing down the position of every single Crop you have planted and would work as well.
Unfortunately, in the early stages of farming, when I did not have sufficient Yellow Wonderfuls to smash all the rugged boulders in my Field (requiring 2 Yellow Wonderfuls in your Hammer), I simply sowed a new Crop whenever I harvested an old one, because space was limited and I wanted to reach the 100 shipping requirement for each Crop that unlocked new Crops. Doing this resulted in many fatalities, wasting both seeds and money. If you divide your Field in half from the start of the game, you will be more successful. Do the same with respect to your Greenhouse.
An easy and logical method of division would be to place all the Crops that require MORE water on the West side of your Field, closest to the River. Place the Crops that require LESS water on the East side of the Field, as far from the initial water source as possible. To use the same logic with respect to Crops in your Greenhouse, however, you would have to reverse the positions as the Water Spigot is on the East Side of the Greenhouse.
Whatever you do, be consistent in placement of Crops to avoid tragedy. It may be easiest to place all Crops that require more Water in the West, whether in the Field or the Greenhouse. W for Water, W for West... After all, no time passes in the Greenhouse. It is easy enough to reach the Water Spigot from either side of the Greenhouse and conformity in both Field and Greenhouse requires less thought.
There is nothing more heartbreaking than the sight of an empty plot that was sown with rare seeds obtained from an item from Manfred that has not been unlocked in your game! For example, even where Grains are concerned, they do not follow the same rules. Soybeans require MORE water, but other Grains require LESS. You will kill off your Wheat by overwatering it and delay the harvest of your Soybeans if you do not water them sufficiently. Avoid tragedy and heartbreak with a simple Farming Planogram.