QuestionsHow to growVegetable GrowingBulb OnionsMoss growth on driveway and seed onions 0 Vote Up Vote Down Gerard Buckley asked 15 years ago Can you advise regarding moss growth on tarmacadam driveway? Also what is the best time to plant seed onions? 1 Answers 0 Vote Up Vote Down Gerry Daly Staff answered 7 years ago Sow onion seeds in March ideally in fine soil, or sow 5 or 6 seeds in cell trays or small pots and plant out the group of seeldings later. Use Mossgo or similar product for driveway moss.