Prompt freezing will well preserve your homegrown beans’ vitamin content. The key to successful bean freezing is carefully timed blanching. First, bring your water to a rolling boil. Then add no more beans than the water will take and still remain boiling. After 3 minutes (not a moment more, or they’ll be limp when they come out of the freezer), remove the beans and immerse them in ice water. When they’re cool, blot dry and pack into meal-size portions in plastic freezer bags.