If you've harvested your fruits and vegetables, but can't eat them all, don't let them go to waste. When they're at their peak flavor and ripeness, can them. Canning is a great way to store your garden produce. You can even can produce from your farmer's market. Canned produce will keep up to a year if done properly. Also, canning is a fun family project.
Canning is really just heat processing. It involves placing food in sealable jars, which you then heat for a while, and cool later. Heating up the jars kills the microorganisms that cause spoilage. When the jars cool, air pressure seals the containers tight. This keeps out other microorganisms.
Canning uses mason jars, not tin cans. If you're canning foods with high acidity, such as tomatoes, you'll use a boiling water canner. For low-acid foods, such as green beans, use a pressure canner.
You don't have to stick to plain fruits and vegetables when you can. Add spices, herbs, and other items to make salsa, side courses, and soups. The idea is to be as creative as you want with the produce you have.
There are several steps to preparing foods before you begin canning them. They're a great excuse to invite your kids to work on a fun project. The whole family will enjoy spending time together canning the food, and then eating it in the months to come.
The internet is full of great places you can visit to find out specific instructions and recipes for canning. The USDA lists several, including http://foodsafety.cas.psu.edu/canningguide.html.