How to Divide Perennials

September 30, 2015 How to Divide Perennials

Most gardening experts say that you should divide your perennials periodically, to maintain optimum health. Why is this? Dividing perennials controls the size of the plants, rejuvenates old plants, and also gives you more plants!

However, if you are a new homeowner and newbie gardener, perhaps you have wondered just how and when to do it. The good news is, dividing perennials is a fairly simple task, and it doesn’t need to be done every year. Follow the steps below, and your perennials will stay beautiful and healthy for many years to come.

When to Divide

You’ll want to divide perennials about every three to five years. If they are overgrown, you will certainly want to divide them. However, a good general practice is to divide them before they become overgrown, in the year when they look their best.
You can do the division in the spring or in the fall. Fall bloomers should be divided in the spring, and spring bloomers should be divided in the fall, as it best to do it when they are not flowering.

How to Divide

First, prepare the area where you will be replanting. This will minimize the time that the plants need to be out of the ground.
Using a spade or pointed shovel, remove the parent plant from the ground.
To be able to see the type of root system that the plant has, you’ll want to hose it off or just shake off most of the dirt. The type of root system will help to determine just how you divide the plant. For a complete guide, with pictures, to different types of perennial root systems, check out this handy guide from Clemson University Extension.

How to Replant

Keep the roots of the divisions cool and moist until you can replant them. A good way to do this is to cover them with dampened newspaper. Try to get them back into the ground as quickly as possible, however.
You will want to make sure that the divisions are small. The ideal size is 20-25% of the parent plant.
Dig a wide hole to replant the divisions. This is because you will want to spread the roots out when you replant. Crowding the roots will interfere with healthy regrowth. A good guideline is that the hole should be slightly wider than the roots when they are spread out on all sides.
Be sure to add a generous amount of compost.

Tip: You may not have enough room in your garden to replant all your divisions. This is the time to call your friends who might like some of your asters, hostas, or dahlias for their own gardens. Spread the wealth and the joy of a beautiful perennial garden!