How to divide ornamental grass

I divided a few clumps of my ornamental grass this summer and took a few pictures to show how it was done. The pictures are of my absolute favorite grass, Gracillimus (Miscanthus sinensis ‘Gracillimus’ – Maiden Grass). I just love how it has a vase-like shape and the fine leaves sway with the slightest breeze. It looks awesome all winter long too which gives me something to look at other than plain white snow.

One thing to keep in mind when dividing ornamental grass is to do it during it’s active growing cycle. For warm weather grass like Gracillimus, that is during spring to mid-summer. For cool season grass, spring and early fall is the best time. Just remember to keep the divisions well watered for the first year regardless of when you do the dividing. That being said, I have successfully divided and planted some warm weather grass in early September by keeping it well watered until the ground froze, but don’t recommend doing so.

This first picture shows the clump before it was divided. Notice how large and round it is. This clump was planted just a few years ago and was about a foot or so in diameter.

Ornamental grass before dividing

This picture shows the tools I used. A sturdy shovel and a sawzall with a coarse toothed blade. Notice that the shovel is a flat bladed spade, not the curved spade that most homeowners have. The flat blade makes it much easier to cut through the clump. Truth be told, I don’t own a curved spade anymore. Once I began using the flat bladed one I realized I never wanted to use the curved one again.

tools for dividing ornamental grass

Here I am undercutting the clump. I am digging down and severing any roots that are in the way. I will also be using this cut to pry up the clump I am trying to cut off.

digging ornamental grass

Here I am using the sawzall to cut through the top of the clump. In the past I just kept jumping up and down on the spade but decided to try the sawzall this time because I nearly killed myself cutting through the clump with just the shovel.

digging and cutting ornamental grass

And now for a friendly warning about dividing ornamental grass: be very careful! The next picture will show you just how sharp the edges of the leaves can be. The wound was surprisingly deep for being done by a blade of grass!

Ornamental grass is sharp!

This picture shows the root system that was cut using the sawzall. You can see just how dense the roots are and can imagine how tough it is to divide a clump like this with just a shovel. As I mentioned before, I did exactly that the last time and about died from the exertion! I recommend the sawzall over just using the spade to cut through these hard, dense roots.

Ornamental grass roots

This picture shows how much of the original clump I removed. It turned out to be about 1/3 of the original clump. I just filled in the hole with soil so the clump would begin to grow into it.

Ornamental grass after division

Next, I divided the large divisions I just removed into smaller pieces using the sawzall.

Cutting ornamental grass divisions into smaller clumps

The next picture shows just how big these divisions are. Each one is almost as large as the original clump of grass I planted a few years ago!

Large ornamental grass divisions

This last picture shows the 4 large clumps I ended up with that I planted in various locations on my property. In just a few years, each one will be just as big as the original plant I removed them from. I can’t wait!

Ornamental grass divisions

Do you have any tips on dividing ornamental grasses?


How to divide ornamental grass — 1 Comment

  1. A sawzall. great tip! I divided some feathered reed grass last year, and holy cow was it a job! a sawzall would have really helped and done a cleaner job. I agree with you on that spade. I purchased an $80 ‘king of spades’ spade (yes i said 80) and I will never go back. Its true what they say about the right tools.

    Since I started dividing every year, it seems the more you let them sit, the harder they are to separate. I know not everyone can get out there and divide all their grass, and not everyone would want to. So those powertools can come in real handy!

    You have some beautiful (and sharp) grass. I love the photos too, well done!