How and When to Divide Hosta Plants

A healthy hosta is easy to divide into more plants so you can add more of this perennial's lush beauty to your shade garden. And if done correctly and at the right time, they rebound quickly and begin growing more gorgeous foliage for you. Starting with a good-sized hosta, you can divide it into several plants, perfect for grouping beneath a tree or shrub or lining a shady path. This guide will show you how and when to divide hostas to ensure success.

When to Divide Hostas

The best times to divide a hosta are in spring, as new growth emerges, or in fall as growth begins to slow down.

Dividing Hostas in Spring

In spring, you can divide your plants from the time you first spot their “eyes” popping up through the soil until the leaves begin to unfurl, which gives you about a month. When dividing in spring, don't worry if a few leaves get damaged; just remove the injured leaves if this happens.

Dividing Hostas in Fall

For fall division, you have a similar four-week window of opportunity. You should wait until night temperatures have cooled but while there is still time for divisions to grow new roots before freezing weather sets in. September is usually best in areas with cooler climates, October is okay for dividing hostas in warmer zones.

How to Divide Hostas

1. Water the hosta. If you haven’t had rain in the past day or two, a thorough soaking the day before you plan to divide your plant will reduce stress on it. 
2. Dig up the entire clump. Using a spade and/or garden fork, dig six to eight inches outside of the crown of the plant. Depending on the hosta variety, the root system may extend eight to 18 inches deep. Starting from one side and working your way around, dig beneath the roots. then ease the clump out of the ground. If you're unable to dig up the entire clump in one piece, cut through it with a sharp spade and remove the separate pieces.
3.  Remove excess soil. Once you've gotten the clump out of the ground, remove extra soil from the root ball to make it easier to work with. Use a garden hose to wash some of the soil off the clump before cutting so you can see the eyes more clearly and avoid injuring them.
4. Cut the clump into pieces. Use a sharp spade or garden knife to cut through it, trying to avoid cutting through eyes or roots. A large clump can be divided into several smaller sections; just be sure each one contains at least one eye (two or three is better). If you don’t need a lot of new plants, just divide the clump in half, thirds, or quarters—these will rebound quickly, while smaller divisions may take a couple years to fill out.
5.  Clean and soak the divisions. Remove any broken roots and damaged or dead leaves. Also look for weeds sprouting from the remaining soil and get rid of them. Place the divisions in a bucket of water for 5 to 10 minutes before planting.
6.  Prepare the new planting holes. You may not be dividing your hosta again for several years, so be sure to prepare the soil well. Select a shady site, ideally with good drainage. Be sure the planting holes are large enough to accommodate the entire root system and work some compost into the soil.
7. Plant and water the divisions. Set the divisions so that they are at the same depth as they were growing before they were dug and fill the hole with soil. Water them well to eliminate air pockets. Water spring-divided plants regularly until established. Fall-divided plants require less frequent watering.