365 Days to maturity (2nd Year). Alcea rosea ’Nigra’. Hollyhock Nigra Flower Seeds. Non-GMO, open-pollinated, self-seeding short-term perennial (sometimes considered a biennial). Nigra hollyhock flowers are not easy to forget. These extra tall flower stalks display dark maroon flower petals that look nearly black. The centers of the flowers have a contrasting yellow throat for even more visual interest. Expect ten or more blooms per stalk coming on throughout mid and late summer on these vigorous and spectacular performers. Approx 3,000 seeds per ounce.