Kale

Kale is the vegetable that keeps giving after everything else in the garden has quit. It handles frost, heat, poor soil, and neglect. Lacinato (dinosaur) kale and Red Russian are the tastiest varieties for beginners. It's a cut-and-come-again crop that can produce leaves for 6+ months. In many climates it overwinters, and frost actually makes it sweeter by converting starches to sugars. The superfood hype is real — one cup has more vitamin C than an orange.