Among many garden chores that come in spring perhaps the biggest is the trimming of the ornamental grasses. Trimming back perennials can be time consuming but the ornamental grasses can be a bear. It’s not the tiny little hair-like strands of the Nassella tenuissima (Ponytail grass), or the tall and narrow ‘Karl Foerster’ Feather Reed Grasses. The panicums aren’t a problem either, both ‘Northwind’ and ‘Shenandoah’ switchgrasses are relatively tame. The muhly grass is very cooperative. It’s the miscanthus. I know someone is probably thinking “Dave shouldn’t plant that, it’s invasive” and you would be right, it is and I shouldn’t, and I won’t – at least not anymore. I’m switching to the panicums as a replacement for miscanthus but I still have to tend the miscanthus I have even if I never add another one to the landscape.
Pruning an Ornamental Grass
Trimming back an ornamental grass is fairly straight forward. For miscanthus I trim down to 6 inches or so high and take small handfuls of grass at a time then prune them with my hand clippers. For other grasses I make sure to stay 4-6 inches above the crown of the plant. I kind of use the top of the green growth as a guideline. As far as tools go I use the low-tech hand clipper option, but I don’t recommend it! It wears out your arm very fast and the clipper blades even faster. A good pair of electric trimmers will make “short” work of your grasses but a pair of sharp pruners will do a good job too. I also recommend using good thick gloves or you risk a painful death by a thousand paper cuts. It’s not really paper, and you won’t really die, but paper cuts are one of the most annoying injuries you can receive and these grasses have very sharp edges.
It's been too cold, but I have Miscanthus Udine and Panicum Northwind. Both are a real chore to cut down. I agree with you, the hand pruners work better in small bunches. I am not looking forward to it, and then the cleanup!!!
Paper cuts and grass blade cuts are about the same in my book. Painful!!! I never touch the pampas grass but some people cut theirs and some dont. I say, if you dont need to cut it, then why cut it? I am not sure why some people cut the pampas down here as it is very sharp. I have cut the liriope in the past but have not cut it in two years and it looks fine to my eyes. I may have to clip it this year as we have had a really cold winter and that may make all the difference come spring. At least the Liriope is not sharp to the touch…
I have the Shenandoah, Purple Fountain & a couple others. Guess I need to trim them now. Should I trim the Lemon Grass at this time also? {If it's still alive}
I've got my Adagio all cut back (okay, most of it anyhow). I've not had it self seed. I think it is only a few grasses that do that. I thought the pennisetums were the worst? Have you had trouble with miscanthus?
Hi Dave
I've got Miscanthus 'Juli' and zebra grass. I pretty much cut them in the same way as you.
I have no problem with them seeding.
Stipa tenuissima seeds too easily.
Stipa calamagrostis, or pheasant grass is a bit of a thug as it spreads underground. I planted three sections on this on either side of the pergola and it pops new shoots all over, practically taking over. That said, I reckon I should be able to cut sections of it brutally with a spade without any bother and have new plants easily. It's a beautiful grass and if I was planting a naturalistic prairie scheme(which I'm not), it'd be first on my list as it quickly covers the area.
Dear Dave (sorry I haven't been by more often .. a few weeks of UGH ! happened 🙂
I love my miscanthus and it is not invasive here .. and YES ! now is the time coming up to trim back all these beautiful grasses .. I did learn a hard lesson one year of do NOT trim back fescue .. talk about the bowl on the head BAD haircut ? eeeekkkk ! Leave those guys along !! LOL
Joy : )
GG,
The cold has been very prolonged this year. Very frustrating! The cleanup is a bear but just think of all the great compost material you'll get!
Skeeter,
I don't mess with pampass! Don't have any here. They seem too large to me. The liriope I need to get to soon! The rabbits haven't been earning their keep. 😉
Lola,
I wouldn't worry too much about the lemon grass, just cut back any dead stuff.
Tina,
Pennisetums are pretty bad but the miscanthus is on the invasives list – at least it was last time I checked. I really haven't had any trouble with the miscanthus at all and I do like it. It's just the idea of having a potentially invasive plant in the yard that has me cautious.
Rob,
I haven't noticed a problem with seeding here but they are something to keep an eye on. Our state has a Exotic Pest Plant list that has some garden favorites on it.
I really do like the stipa, even if it does reseed!
Joy,
No problem, I haven't been visiting Canada much either, with the Olympics on I could see it almost all the time ;). Your climate is probably slows down the spread of miscanthus and tames it!
My garden guru, who gave me a nice zebra grass, advised hacking it down to the few inches and then burning it to the ground. This would be at the end of winter, before the new shoots emerge. I won't be trying that this year, but in I'm sure I will in the future. Right now, I have too many leaves mulching that garden and wouldn't want to lose control of the fire. When the current snow melts, it's the pruners for that miscanthus.
Let me add that if possible choose a non windy day or watch those grass blades blow all over the place! gail
I usually just sic a family of ravenous beavers on my miscanthus and they make pretty quick work of it.
Speaking of miscanthus being invasive, did you know that several state universities are working with miscanthus to make biofuel? Miscanthus will save the world!
Kate,
I've never intentionally burned anything I wanted to keep! I'm sure it will help some plants but I don't think it's necessary. It sounds a little too risky to me!
Gail,
That is definitely true! Fortunately the day I chopped it back wasn't too windy.
Steve,
I knew some UT scientists were working on Switchgrass and some guys in Chattanooga were working on kudzu. I don't know why when there are so many viable options we insist on using corn for fuel which we need in the food supply. Those invasives really could do some good!
Not all Miscanthus grasses are invasive. Teh species can cause problems, but cultivars usually do not reseed. Here is a good article from the University of Minnesota about invasive Miscanthus.
http://www.horticulture.umn.edu/miscanthus/
Melody,
You're right, not all are invasive and it always depends on growing conditions but here in TN at least three varieties of Miscanthus are listed on the invasive list, one of which I know have in Miscanthus zebrinus. The average consumer needs to know the potential the species has – that it could be invasive. The site you posted has some very good information but it clearly states the concerns for the plant on the Recommendations for Using Miscanthus page. It also says: "Recommend alternative native grasses such as Indian grass, Sorghastrum nutans, or switchgrass, Panicum virgatum" which is what I mentioned in the post. I really like Miscanthus and I would use it liberally if it didn't have dangerous potential as an invasive plant – although like Steve said, maybe it could save the world!