[James Kilkelly]

Divide grasses, How to, When, and which ones.
by GPI

Have you given any attention to your grass yet this year? No, I don't mean lawn grass, as the middle of March is time enough to start thinking about this green carpet. I'm talking instead about ornamental grasses.

Over the past ten years or so ornamental grasses have become extremely popular. From lowly sedges (Carex) and Oat Grass (Helictotrichon) to the big Momma's like pampas grass (Cortaderia), you will usually find at least one if not a cluster of grasses in the average garden. Gardeners have cottoned on to the fact that carefully selected grasses are a wonderful way to add splendour and colour to their gardens without a great deal of effort.

Other benefits of selected ornamental grasses include....

· Their resistance to pests and diseases.
· Hardiness to frosts and cold winds.
· Year-round interest.
· Speed of growth and strength.
· Adaptability to a wide range of soil types and garden styles.
· Their ability to have movement by swaying gently in the lightest of breezes.
· Add to this the soothing sound they produce as they rustle in the wind.

But probably the biggest bonus for any gardener, especially a cash-strapped one, is the fact that ornamental grasses can be divided to produce more plants. No need to grow from seed, or care for seedlings, just to divide and multiply.

Which brings me back to my original query "Have you given any attention to your grass yet this year?" That's because cool climate grasses are best divided around now, mid-February through March. This late winter to early spring division carried out just as they come into growth suits them best.


Carex testacea (New Zealand sedge), photo / pic / image.

Cool climate grasses.
What are the cool climate grasses? Grasses from cool climates include Carex, Festuca, Helictotrichon, Stipa, Chasmanthium, Deschampsia, Calamagrostis, Hakonechloa, and Molinia. Dividing these grasses every three years not only provides you with free plants, but prevents root overcrowding and loss of vigour on the parent plant.

Here's how I go about dividing them...
Carry out all division on a "soft" day, by which I mean a damp day with damp soil and no harsh drying winds. This is because your first task is to carefully dig up the grass clump, thus exposing it to the air.

Small, soft rooted grasses can be pulled apart simply by using your hands. If the clump is tough use two garden forks inserted back to back in the middle of the cluster, then lever them apart. On a very tough rootstock you may even have to chop with a sharp spade, hatchet, axe, or cut it with a sharp knife or saw.

Make sure each division has several healthy buds or shoots and a reasonable amount of root attached. Select larger divisions (12.5cm/5in or larger) for replanting throughout your garden. You should use a half topsoil and half compost back-fill mix for transplanting, working this around the transplant in the pit with your fingers to eliminate any air pockets.

Your smaller divisions can be potted up for growing on, then planting out later. John Innes No 2 compost would be my preferred potting medium in such a case. Water the transplant heavily (potted or planted) and ensure you water well for its first year.

The other grasses you may come across are the warm climate grasses. These don't come into growth until later, so you are best holding off until May before dividing them.

Need materials? Irish home delivery.	Need materials? UK home delivery.	Need materials? US home delivery.

Warm climate grasses.
Grasses from warm climates include Cortaderia, Miscanthus, Phalaris, Arundo, Imperata, Panicum, Pennisetum and Spartina.These warm climate grasses rarely require division to prevent root overcrowding, say once every seven years or so. But many gardeners will divide them more frequently to access some free plants.

Grasses from warm climates are divided in the exact same manner as the cool climate grasses. However, extreme care must be exercised when handling pampas grass (Cortaderia selloana) as it has razor-sharp leaves. Stout gloves and long sleeves are a necessity when dealing with this beast.

Good luck with your grass dividing.

Any queries or comments on Divide grasses, How to, When, and which ones, please post below.

[Sive]

Thanks for that....I'm new to growing grasses and need all the advice I can get. Now we just need slightly warmer weather to get started on all this work.

[f&vlady]

Hi, brill timing on that article as I was going to post a query regarding same. Would gladly welcome that "soft day" you mentioned, brrrrrrrrrrrrrr, it's freezing here!
f&vlady.

[James Kilkelly]

Enjoy, duffle up well and get out there on the next "soft" day with spade, hatchet, axe, sharp knife and saw strapped to you.

[Protein]

I have a 9 year old clump of Pampas grass (Cortaderia selloana), and although it does "flower", I feel its a bit tired looking. Question is should it be cut down to encourage new vigorous growth? If so, when is the best time to do this?

Additionally, I have heard some people burn it down, does anyone know if there is a method in this madness?

Not in reference to Pampas, but could I easily propagate Carex grasses by seed?

me x

[medieval knievel]

[James Kilkelly]

Brilliant pampas grass burning tips here from our resident blackbird........ http://www.gardenplansireland.com/forum/viewtopic.php?p=2653#2653

[andy1005]

Hi ,

Just thought I'd say very nice article and right down our street given what we do. Would love to maybe use that (with references of course) don't know if that's possible.