Hostas are a shade tolerant plants that produce attractive foliage. Some varieties grow up to 3 feet tall and wide and others grow only a few inches high. A hosta reaches maturity in about 8 years, but they can be divided after the first three years to make new plants for the garden.
Choosing the Right Time of Year
Hostas should be divided when they are actively growing and the soil is warm so new roots can get established. Separating hostas in the spring may cause new divisions to be replanted in cool soil, so the early fall is the best time to divide hostas. Pick a day when there are about 60 days left before your average first frost date. This is late August in most areas of the U.S. New divisions planted this time of year will need a constant source of moisture to get established.
Digging the Hosta before Dividing
Dig the hosta from the ground using a sharp shovel. Dig under and around the hosta in a way that will not disturb the roots or cut through the root system. You may notice that some smaller divisions fall off when the hosta is removed from the ground. These can be planted right away.
Identify the Eyes of New Plants
After removing the hosta plant from the ground, wash the dirt off the area just above the root system where new buds, or "eyes," are visible. Wash off the dirt from the entire root ball only if necessary in order to identify where the divisions are located.
Separating the Hosta Plant
Try to gently twist and pull the hosta roots apart in a way that the new root divisions will include at least one or two eyes. If the root base is difficult to separate, use a sharp knife to gently slice the area between the divisions, being careful not to damage the new root division that you can easily see. Immediately plant the new divisions in moist soil. Do not let the new divisions dry out for even a few minutes.