How to divide day lilies in pots
1 Decant the plant from the container and remove any weeds or moss from the surface of the compost. Cut off any old flower stems and damaged foliage. 2 Divide root balls into the required amount of sections. If you cannot tease the roots apart by hand, use an old bread knife to slice through them. 3 Pot sections into containers large enough to accommodate the root systems. Use a mixture of multi-purpose compost and John Innes compost.