Some plants require more while others prefer less.
Each of these will affect how quickly your garden dries and how often you will have to replenish it. Some sprinklers have a volume gauge built that you can set for the amount of you want to fall on your garden. If you don't have one try making a rain gauge . It will measure how much the garden receives when you it or it rains. Use any clean, straight-sided container like a soup can or a glass jar.