Here in central Texas, Sept. and Oct. have been very dry, with less than 1" of rain over six weeks. Most of our friends and neighbors given up on their gardens. We still have vegetables growing because we harvest rainwater when we get it, store it and use it to keep our plants alive and producing. We were talking to our local agricultural agent, and he said more and more farmers and ranchers were harvesting rainwater to water crops or livestock. They are doing it on a large scale, while we are harvesting on a small scale, but the benefit of having water when needed works for all of us. He said that it is important to have water when you need it, and in the near future, having water when you need it may be "iffy". If you are in an area prone to droughts, either temporary or long-lasting, you might want to look into harvesting rainwater for use during the dry times.
We don't need to harvest rain water here In Scotland but I do it anyway to water the plants in the greenhouse. As for the garden - well it get well supplied from Mother Nature and it's seldom we have to water it ourselves.
I harvest water with my rain barrels. I really love having the recycled water to use in my gardens. I've been fortunate here in Nebraska this year; as we have had nice timely rains, but I always fill up the barrels when they are down and rain comes. We are certainly no strangers to drought here and have had water restrictions. We mustn't ever take water for granted!!
I have 5 - 55 gallon barrels hooked up to the gutters in the front and back with one more to hook up out front this fall...after the government budget is approved meaning the government will not shut down then I can start saving up to buy one of the larger ones.