A beginner’s guide to dividing hostas
Dividing hostas is a great way to multiply your plants. Whether you’re planning a big hosta garden, sharing them with friends, or donating them to the local plant sale, there are always lots of gardeners looking for more hostas!
Hostas are commonly divided in spring but can be divided any time of year. These plants can be divided by digging the whole clump of roots up or by doing the division with the plant in the ground.
To divide the entire plant, dig up the clump and use a garden fork and shovel to split the crown down the middle into two or more pieces. If you need only one baby hosta from a mother plant, leave the plant in the ground and take a triangular slice out of the base (like a pizza). Re-pot the slice on its own and refill the hole in the mother plant with rich organic soil.
Read on to learn all about dividing hostas.
Dividing hostas: the basics
Hostas are among the easiest perennial plants to divide. This is a great project for beginners and for gardeners looking to multiply their existing hosta collection to cover a larger area or to share the divided baby hosta plants with friends or the garden club.
When to divide hostas
Hostas are usually divided in the spring, just as the shoots start to emerge from the soil. The division is most common when the shoots are several inches high and often still have a purple tone. This is the ideal time to divide the plants as the roots are actively growing and better able to re-establish themselves.
You can, however, divide hostas reliably at any time of year except for fall, just before frost is expected in your area. Fall division can result in damage to the crown and buds over winter if the replanted roots are subjected to repeated freeze-thaw cycles in the soil. That said, even fall division of hostas can be successful, so it is worth a try if this is the only time of year that works in your situation. Otherwise, wait until the ground thaws in the spring to divide your hostas.
How to divide hostas
Hostas can be divided by digging up the entire plant and cutting the roots up into pieces, or you can simply take out a bit of the base without digging up the entire plant. Digging up the entire plant works best if you have to transplant the hosta to a new location anyways, or if you need quite a few divisions from the mother plant. Taking a slice out of the base without digging the plant up is best for making one or two baby hostas without significantly slowing the growth of the mother plant.
Digging up and dividing hostas into pieces
Start with a healthy hosta plant that has been watered consistently. Pull back the mulch so that the surface of the soil is visible. Start digging a circle around the hosta, as least as wide as the leaves of the plant tend to grow in an average season. Hosta roots generally grow wider than the aboveground foliage, and it makes sense to try and keep the plant as intact as possible at this point.
Pull the entire clump out of the ground. Use two garden tools, such as a fork and a shovel, to split the clump in two. This is easiest if you place the tools back to back. Alternatively, a cutting tool like a sod knife, hori hori, or even a sharp spade can be used to split the crown down the middle.
Each half of the crown can be divided up into smaller pieces. You can continue dividing each piece if desired. This is easiest if you wash the roots with water so you can see where the buds are at the top of the root crown. Divisions can be made up to the point where each piece has only one stem bud, although these small divisions will take several years to grow to an appreciable size.
Once the divisions have been made, replant immediately. You can replant them into the garden bed or pot them up in containers. Water thoroughly after planting.
Dividing hostas in the ground
Start with a healthy, well-watered hosta. Examine the base of the plant, which should be somewhat circular. Use a sharp flat spade to cut into the base of the plant from the side into the center. The goal is to take a “slice” out of the base, rather like a pizza slice. This slice should have a bit of the central crown, including some buds, as well as some tuberous roots hanging down from the bit of the central bud crown.
Pot up the slice in its own pot or in a new spot in the garden. Go back to the mother plant and refill the slice’s hole with rich organic potting mix or compost. Water both plants well after dividing them.
