Dividing hostas is easily achieved. Most home gardeners will propagate their hostas by division. Hosta division should be done when no shoots are growing from the center of the mature clump as this bare area detracts from the appearance of the plant. Dividing hostas this way will improve the plants appearance. Lift the entire hosta clump and wash the soil from the roots to make it easier to see where to cut and divide the clump. Use a sharp knife to make the cuts for dividing the hosta. Place the divided plants in their planting holes and keep them well watered for the first two weeks.
Spring is a good time for dividing hostas because the new shoots are only a few inches high and the leaves have not expanded. Spring division may cause leaf wilting on warm days, since the roots have been reduced in size or they were cut while dividing the hosta.
The month of August is also a good time for dividing hostas. The warm soil and humid weather promotes better root growth. The divided plants can get established before winter sets in. The hot weather usually experienced in August will create a high demand for water. Keep the plants very moist for the first two weeks after plant division.