The Black Tail Mountain Watermelon is one of the best-tasting melons we've ever tried! Black Tail variety is extremely well suited for northern zones especially but can also stand the higher temperatures and droughts in lower zones. The dark green/black rind conceals a gorgeous deep scarlet red flesh that is sweet, crunchy, and super juicy. The round fruits can weigh between 8-14 lbs. and usually measure between 10"-12". Citrullus lanatus. 80 Days to Maturity.