QuestionsHow to growFlowersSummer colour from seedsunflowers 0 Vote Up Vote Down dereck phelan asked 16 years ago I planted a large number of sunflowers this year and they are about 1.5m high at the moment 1 Answers 0 Vote Up Vote Down Gerry Daly Staff answered 6 years ago No, sunflowers are annuals … grow up, flower and die in the same year. But they are easily raised from seeds sown in spring, as you know