Hawk...it depends on what kind of OG it is. Warm season growers should be cut back to within a few inches of the ground, and cool season growers should be cut back by 2/3's of their full height. Both can be done anytime from mid-winter to early spring. This is a very general rule, and there are exceptions.

I would consider leaving it for winter interest so you can enjoy it for one more season before cutting it back. :)
Pam

Which grasses do you grow? We could give more specific information if we knew that, plus tips about cutting back and then dividing (should that also be desired).

Donn -

I have never read or heard anyone say cool season grasses get cut back 2/3 of full height.

I've always cut all my grasses to the 6-8" above ground rule. In the spring when new growth starts showing.

But as you stated there is no tried and true rule stating "this way or everythings dies" method of cutting back grasses.

I just enjoy watching them grow. Ornamental grasses, a mans perennial. Cut 'em back, grab a 'freshment, grab a chair and watch 'em grow".

Jake

Jake,

Greenlee, page 20, 2nd column, 2nd paragraph.

Donn -

That book is one of my first grass books. It's amazing how one forgets what they read several years back.

Now I need to start rereading all nine books to revitalize the brain, plus whatever pamphlets that I got squirreled away also.

Thanks for making me do the research of the archives. ItÂs always a pleasure to be pushed by others interested in the same topic or ornamental grasses.

Jake

Spent the day cutting back a combination of warm and cool season grasses,my learned rule is 'generally no less than one foot height should be left standing',as the new growth sprouts through the old stalks...my "cutting back" tip is to tie the standing growth tightly about halfway up the stalks,and cut below that ; leaving a bale as it were for easy transport to the compost etc,especially helpful in a windy garden with multiple stands of grasses.Perhaps I'm the last in the gardening world to stumble on to this notion,just thought I'd share;really helps speed up the cutting back process.

Katt -

Leaving a foot of stubble is more than most recommend on warm season grasses. Cool season grasses this would be okay.

My comments are made from my experiences. You being located in z5b I would think you are missing some of the fine winter scenes by cutting back your grasses in the fall.

Yoor zone may not get much snow cover but even some would be very interesting as it sits atop the past seasons strands of grass left standing.

Part of the beauty of ornamental grasses is the autum and winter structure of grasses.

Comne spring time when the dead fronds start to break and fly around then the OG's get ugly.

As for your method of tying the grasses up and cutting them we've been doing that for the past 9-10 years.

Because we can't burn in our area we haul the fronds to the dump and this requires at least one fully loaded and tied down pickup load if not more.

Jake

Wow Donn, I never knew that about cool season grasses. I have always cut them back like the others. But maybe by cutting back they mean the foliage and not the spikes. In otherwords, when cutting back my Calamagrostis, i should cut the 2/3's of the gree foliage back, not 2/3's of the either height. Does that make sence ? That would seem a bit more feasable to me.

just my $.02

Blackie

I think I must tell this to the mice, who mow my (semi-evergreen) cool season grasses down to the nubs over winter. Those same grasses come back with a vengeance in spring. Last winter some Deschampsia were chewed back by the mice (voles, whatever they were) and some plants were left in tact which I then cut back in spring. Neither looked any different from the other. They also mowed down the Blue Oat Grass - a plant which I have been nursing and fretting over for a few years and it did very little. This year, after the mice did their thing, it tripled in size and was beautiful. When I grew fescues (I no longer do) the mice also ate these, and the plants were no worse off. I generally in spring cut back all my grasses that the mice don't get to about 4" above the crown and I normally get them cut back before new growth starts. I've never lost a plant by cutting it back more than 2/3.

I wouldn't be in agreement with this 2/3 recommendation. I, too, have not heard of it before. What would be the reasoning? To me, I would think quite the opposite - that cutting back as much as possible without damaging the crown would be the best route. What about burning? That gets it right down to nothing. Or animal grazing? Sorry, don't mean to be difficult, but I don't understand this thought. I don't have the book - does John Greenlee explain further?

"Most grasses ahould be cut back to within a few inches of the ground. Some grasses, usually cool-season grasses, do not like to be sheared too closely. Many feather grasses (Stipa spp.), for example, resent a close cut. Often, plants shorn too closely will not recover. To be safe, unless you have been successful in the past, cut back cool-season grasses to two-thirds of their full size." (emphasis added).

That's the whole paragraph, and the reason I said the 'rules' are very general, and there are exceptions. Since we still don't know what flavors we're talking about, general rules are safer, eh?

PS...I always assume that when height is quoted for maintenance purposes, it refers to foliage height, but who knows?

Donn -

Could you give me the ISBN# for the Greenlee book?
I tried to Google it and came away empty.

Thanks and Happy Thanksgiving!

Gej

The Encyclopedia of Ornamental Grasses
0-87596-100-2
Rodale Publishing

Here is a link that might be useful: Amazon listing

Thanks, Donn, for posting the paragraph. I'm curious - do you (or does anyone) follow that recommendation and, if so, do you find any difference - better or worse?

Thanks Donn!

I too had the book but didn't think to look until you wrote. Page 20 says it all but I've always cut back the same regardless of cool or warm. Same result for both... beautiful grasses every year. Maybe IÂve just been lucky?

Pudge...I'm about a year into testing a variety of ways to cut back cool-season growers, but they're all smaller grasses, from Festuca to Deschampsia. For example, I harvested seed from 2 second year F. glauca clumps this year. This left the plume stalks sticking up above the foliage. On one of them, I cut the clump back to ~3" and on the other, I cut it back to 2/3" of the foliage height. The second clump looked better from the start, because the foliage grew back from a taller start, hiding the plume stalks. Today, both clumps are exactly the same size, but the clump that was cut to 2/3 has more dead foliage in it from the hot dry summer. The clump that was cut shorter is much better looking overall. It sat short until the weather cooled off, and then took off.

I have a Deschampsia clump and a Luzula nivea that I'm going to leave until late winter, and then cut them back short. I'm figuring my cool spring will bring them back nicely.

Hi Jake; I have left a few of my own grasses uncut this Fall,the ones sitting in protected spots ,you may not have had the near tornado winds we experienced through Oct/Nov which left ,at least in my clients' gardens a messy pile of half blown down stems which they had no desire to look at through the Winter.As for snow,I live in the snow belt,we get nine or so feet.I too speak from my experience and apprenticeship with a nurseryman.Happy Thanksgiving.

Katt -

That's one lotta snow you get. Being in Z4b-5 we have not gotten anywhere close to what we use to get.

9 feet of snow will definitely cover any grasses that you leave un-cut.

Still a fresh dusting or even 3-4" inches of snow sitting atop of the grasses creates some artistic beauty in a winter scene.

We haven't had the winds in Oct. that you got but we have had some very hard winds compared to normal fall weather conditions.

To you and all the other readers - have a great Thanksgiving.

Ornamental grasses - a man's perennials.

Jake