DIY is all about Fun in the game and training Multiple Skills at once. Try to make a routine of planting crops at night and leave them in the care of Farmers. When you return the next day, you will have thriving crops ready to harvest Re-plant your crops in the morning, do your thing all day, and come back to farming at night. Easy as it gets.
Whether or not to have the Gardeners watch crops depends entirely on you. If you do not have them watch, be sure to water everything that needs it at least once and check the Knowledge Base for things to grow in the Flower patches to give that extra protection. Note that they will have to be fully grown to have the effect, so do not dig them up unless you are changing crops.
Additionally with supercompost, the fertile soil spell will give it a supercompost touch even if there is something growing. The Nature Amulet is a great tool if you are not chain farming in game(Runescape 3 Gold). Use it as a timer while you train other skills. Most patches are near trees for WC/Fm, Fishing spots, or Master Farmers to thieve more seeds. They are also capable of increasing crop yields on plots they are bound to, and can teleport you there if your crops become diseased. If you can not get a Nature Amulet, the Farming Amulet is a cheap alternative, but only has 8 charges.
We are not suggest paying the Gardner for Bushes, but we suggest planting them whenever you can. You will only lose 10-20% of them as long as you Super Compost. Always pay for the Trees. If you are not buying them, they are bit more precious. As they give the most Xp in the game, they are well worth going out and getting the payments(Runescape 3 Gold).