Hablitzia, Caucasus Spinach
Hablitzia tamnoides Newly-discovered as a permaculture crop, this is a perennial vine native to the mountain forests of Eurasia. Survives the winter in Zones 3-7, and in fact it dislikes mild climates. Too new to have an agreed-upon common name, it is a very hardy perennial, growing 6–9' long for 2–3 months in the very early spring when few other edible greens have surfaced. It’s also tasty: both early shoots and subsequent leaves make a delicious and tender spinach-like vegetable without any bitterness. It is native to the understory of temperate forests, so it thrives in partial shade that most vegetables hate.
Put it in dappled shade, or in a position with morning sun only, unless you live in a cool climate (Maine, the Pacific Northwest, and the maritime coastal fog belt.)
Plant the small seeds outdoors in gallon pots in fall or very early spring; they need freezing and cold moist conditions to get them ready to sprout (stratification). Grows slowly the first year. Like many vines, it needs to get a strong root system before the tops can grow rapidly. Takes bitter cold, but is sensitive to flooding, so site on well-drained, humusy soils. Rare. 20 seeds.