The post you're replying to suggests a Victory Garden. While a personal victory garden may not have a big effect on global food supplies, it can absolutely help supplement food for households that are squeezed by higher food prices (which is another side effect of global food shortages).

Victory gardens, also called war gardens or food gardens for defense, were vegetable, fruit, and herb gardens planted at private residences and public parks in the United States, United Kingdom, Canada, Australia and Germany during World War I and World War II. In wartime, governments encouraged people to plant victory gardens not only to supplement their rations but also to boost morale. They were used along with rationing stamps and cards to reduce pressure on the public food supply.