One of the most frequently asked questions is "How much water will I need for my garden?" Well, the answer to that is it depends. What are you growing? How much are you growing? What is your soil like? Are you doing flowers or vegetables? Will it ever stop raining? Will it ever rain again?
So our general answer is, "Start with what you think you need and go from there." OK, so that is not a definitive answer, but it is a start. We started with the idea of getting one barrel seven years ago and ended up ordering 8. Well, we didn't like how they worked so we played with them until we were at least able to use a couple of them. (That experience is what got us started with this business venture!) Since then we have expanded to using large tanks and rain barrels which allow us to harvest about 900 gallons of water. Do we need all that? Right now the answer is, we don't know (see above questions for reference). We are just a third of the way into July and the weather has been wonderful. We are just a third of the way into July and who knows what the weather will be by State Fair time.
One more item on this for now, "With all the rain we've had, why do we need a rain barrel now?" We are just third of the way into July.....
Moral of the story: Better to be prepared than to be without. Have a great summer!