It sounds like you've got hungry rabbits in your garden. Tender young plants in spring are irresistible to them. To scare them off, try whirligigs and wind-powered wood tappers. Human hair and fox urine will make the rabbits believe a predator is in the garden. Blood meal is another option; sprinkle it on the soil around your plants. Finally, you might try a physical barrier like a fence or cages over your plants. Your vegetables are most vulnerable in early spring; if you can make it through the first several weeks, more food sources sprout up elsewhere and your problem may lessen.