Gardening during WWI and WWII was considered a very patriotic thing to do.
During WWI, Europe had severe problems producing enough food for its people.
The farmers were off to work and much of the land became a hazardous war zone, so growing food became very difficult.
North America became responsible for providing food for the people in the countries of the Allied Forces, which meant there were a whole lot of mouths to feed.
The government began to urge people to start a "victory garden" to provide food for themselves and take the burden off the food supply.
In 1917, there were 3 million garden plots, a year later that number shot up to over 5 million plots nationwide.
After WWI many people stopped gardening until WWII came along.
Once again, Americans rose to the challenge of growing their own food.
This time we sent all of our extra food to our American soldiers.