Why Should I Divide Perennials?

Why should I divide perennials, you ask? Have you noticed any of these issues in your garden?

  • you have perennial that is getting to big for its location
  • you have a perennial that doesn't seem to be as stunning as it used to
  • you have a perennial that you love and wish you had some more

If you answered yes to any of these questions, it may be time to divide your perennials.  Dividing your perennials will offer several benefits.

Size Control

You can control the size this way.  Some perennials simply expand forever.  Whether expansion happens quickly or slowly, ultimately you'll have to divide them to control them.  Fear not, this is not a reason to avoid them, you just need to divide them.


When you divide perennials they are forced into sending out more roots and find new soil nearby to gather nutrients without so much competition.  The result will be a healthier plant in the long run which means more blooms.

More of the Best

You get to take your favorites and duplicate them somewhere else in your landscape.  Now that prized perennial out your kitchen window is also visible from the family room.

When Should I Divide Perennials?

Know When to Divide Perennials Like DaylilyOK, so you've decided that you want to divide a perennial for one of the reasons we learned about.  Before you grab a shovel and rip your perennials apart let's learn what time of year this should be done.

Now at this point I could go on to list every possible perennial and tell you the proper season to divide them but I told you this would be simple, didn't I?  So, let's make it simple.

All you need to know is when the perennial blooms.  Spring?  Summer?  Fall? Once you know this apply these rules.


If the primary flowering season is in Spring, divide in late Summer and after the blooms are gone.


For Summer bloomers divide in early Spring when the plants are still small.  Fall is an option here too, but I prefer Spring because they have the whole season to take off.


For Fall bloomers it's easy.  Like the Summer bloomers, divide them in early Spring when the plants are still small.

How Do I Divide Perennials?

Well, there are as many types of perennials as you can imagine so I'll keep this simple and assume that you want to move the division to a new spot in your garden.  If that's not the case, just toss the part you don't want.

I will offer just a couple of tips here though.  Make sure it is not an extremely hot day and that the soil is not waterlogged on the day you want to divide your perennials.  Both of those conditions will make your job harder, and I want this to be easy.

Dividing your perennialsperennials is done in 5 easy steps:

Prepare a Hole

Since you want to split this perennial and put part into a new spot step 1 is to prepare the hole.  Dig a hole a little deeper and about twice as wide as you need to plant the division.  Toss some organic matter or compost into the hole now if you want to and mix it in a little.


Head over to your existing perennial and use a sharp shovel to dig around the drip line of the plant.  Most perennial roots will be within the drip line so you will cause less damage this way than if you angle in towards the plant at its base.  Use the shovel to split the perennial in as many parts as you see fit.  I would not go smaller than one square foot per divided section.


Put some water in your new hole.  Don't make a swimming pool, but don't be shy either.  Your newly divided section will be seeking some water right away.


Set your division in the hole and fill in the soil around it.  The soil line should be at the same height on the plant as it was in its old site.  Try not to bury it too deep or shallow.  Pack the soil lightly around it.  Don't stomp around your perennial to pack the dirt in as that will suffocate the roots.


Dividing Perennials is Easy

Didn't we already do this?  Well, a simple top watering is a good idea here but less important than the water we put in the hole.  At this point you can replace your landscape coverings like mulch or rock if you had any and you're done, but be sure to watch this new little guy for a while and make sure he gets an inch of water per week for a few weeks.

What you do with your old site is up to you.  If you cut around an existing perennial and left part in place you can get away with just replacing the soil around it, giving it a drink of water, and letting it start growing bigger again.  You can also rip is all out and replace it with a part just like your new division, amending the soil along the way.  Either is OK.

Some Closing Thoughts

I have a couple more tips as you move along from here.

Keep Watering

Water for a while.  You'll know once the plant's growth takes off.  At that point you should be fine to let it be. 

Watch How Much You Water

In general, if you see yellow leaves it most likely means you are providing too much water and if you are seeing brown leaves you are not providing enough water.  Naturally, that is not true 100% of the time but don't sweat it.  As long as the plant is growing but has some discolored leaves you can expect it to come roaring back.

Repeating The Process

The difference between a perennial vs. annual vs. biennial when it comes to division is that you don't divide annuals and many biennials self seed and may not need it either. However, most perennials will appreciate being divided every 3-5 years so. Even if you don't want the part you remove do think about dividing them and amending the soil once in a while anyway.  They will reward you with more blooms and be healthier.