QuestionsHow to growFlowersBorder Perennial FlowersDividing ferns 0 Vote Up Vote Down Collins Eileen asked 14 years ago I would like to divide and transplant a very large fern (Dryopteris wallichiana) as it has got too big for where I planted it. Could you please advise me as to how and when I should attempt this? 1 Answers 0 Vote Up Vote Down Gerry Daly Staff answered 7 years ago Large ferns can be divided in spring and re-planted immediately into humusy, well-drained soil and watered regularly until growth is active. Simply split the tuft of growth, using an old knife, or spade if necessary.