This question is asked in the spirit of "I don't know what I don't know".
I have three raised-bed gardens, and I'd like to stop watering them with municipal water and start using collected rain.
Can a [ahem] garden-variety rain barrel supply an adequate amount of water for 12' x 8' of raised garden beds, or would we need to supplement with municipal water anyway? National Geographic estimates that a rain barrel‡ saves 1,300 gallons of water. But I can't find an estimate for how much water is consumed by plants in raised beds.
All of that builds to the real question: what are large-scale options for storing rainwater? Are doubled-up rain barrels effective? Cisterns? Some other concept I've never heard of?
‡-We'll assume 65 gal, though they don't specify