Ornamental grasses are described as cool season or warm season grasses, depending on when they do the bulk of their growing. Pink muhly, Muhlenbergia capillaris, is a warm season grass, meaning it focuses its growth during the warm time of the year - April though September, roughly. In the cooler months - fall through late spring - the grass is essentially dormant with no root or top growth. The recommendation is to avoid planting, transplanting or dividing warm season grasses late in the season (early fall) as there is a risk of no root establishment during the grasses "dormant" period and the grass won't winter over.

If you can be patient, I'd seriously recommend waiting until spring :-)

Oops, my advice was incorrect. Thanks for providing the straight story GardenGal!

beyond the timing issue covered ...

and presuming a large clump ... sharpen your shovel ... stick it in the middle.. and jump on it ...

the sharpening really makes a difference ...

ken

Never dig out or divide a grass while its blooming, no matter what temperature it is.

Gulf muhly is not so bad to dig out and divide comparatively speaking. After spring or late winter trimming back, dig all around the plant and then lift it out as a root ball and knock off the soil. A long serrated knife is a good way to divide it. The new plants will take a growing season to come along, don't expect a lot the first season.

If you dig it out now, it will instantly start turning dead looking as the whole top dies back.

For future reference, the Ornamental Grass forum is active, its just not a daily chat room like the Perennials Forum. The people over there know a lot about ornamental grass issues and check in regularly so your question would have been answered.

Appreciate the input everyone. Looks like I will wait until next spring to dig it up. Bummer.

Texasranger: I figured it would get answered eventually within the ornamental grasses forum, but it was kind of a "do it today/tomorrow or wait until spring" kind of scenario for me. The weather is cool and wet, and I thought it was a good time to transplant, plus it was the only time I was going to be home to do it for the next couple weeks. Normally I would be more patient than that :)

Good luck. I divided some Muhlenbergia riverchonnii last spring and only now are they looking half way decent and putting out good root growth, seems the roots take their time reestablishing unlike some other grasses I grow. The clumps just sat there mostly brown all last summer. M. lindheimeirii and deergrass muhly are the same way. Small young plants will out grow and end up being way ahead of the divisions in my experience.

I purchased a gallon size, and as it turned out, pot bound Gulf Muhly last spring on super sale and its taking forever to come around. It still looks insignificant and ratty with very little green after more than a year. I do better buying 4" potted plants than divisions but they do finally start back up.

I'm getting psyched up to dig out a large M. 'flamingo' coming up in late winter because its blocking the view of the water meter down by the curb. I'm really looking forward to it........

I have a number of large grasses which need dividing...and, it is with huge relief that it is a job I can put off till spring, I use a panel saw to chop the base of the rootball off - a bit like using a serrated knife but more so (I use those cheap ones because the blades always get knackered.

I don't know how critical timing is but I divided my pink muhly grass in fall and the only down side was that it took two seasons to flower again. I was OK with that. I like to dig hole first, THEN, divide and immediately put in new hole and water. It's like plant doesn't have time to realize what has happened and its in the ground again. Keep watered for at least two weeks. I don't think its a big deal to do now unless you care 100% about flowering.