QuestionsHow to growLawnsMossProblem with moss on lawn 0 Vote Up Vote Down Jonathan O\’Connor asked 13 years ago Is November a bad time to apply Iron Sulphate on the lawn to kill out the moss? And lastly When is is a good time to prune (Heavy) the apple trees? 1 Answers 0 Vote Up Vote Down Gerry Daly Staff answered 7 years ago Iron sulphate can be used now for moss control in a lawn. Apples trees can be pruned in winter. Do not prune all in one go, but spread it out over 3 years.