Questions about Giant Reed Grass (Arundo Donax)

[PalmTreesAreCoolYes]

I was recently gifted some arundo donax and I'm having a bit of trouble deciding where to plant it. I already have a few bamboo species I grow and contain rather easily though digging up rhizomes and I will eventually put down some barrier on a couple of them. My first question would be, does arundo donax grow the same way bamboo does and can it be contained the same way? Like could I just rhizome prune with a trench or put down some plastic barrier to contain it? Can it grow in a planter or will it die in one and/or bust out the sides? Could I just rhizome prune it if it was in a planter to prevent it from bowing out the sides and becoming root bound? Can it grow in a fire barrel? I'm thinking about a spot in my yard on the top side of a retaining wall close to my house to plant it. Would it end up pushing out my wall and/or breaking through it? What if I rhizome prune with a spade before it reaches the wall? I've got a decent amount of land so I could plant in other areas if this would be a bad idea.

The person I got it from simply just mows it and I don't think they do anything else. Could I just mow around it like they do or is there some greater unseen consequence to doing that? Can I just step on the new shoots to contain it, like will that stop the rhizomes also from spreading from that point? Are those big plume like flowers that grow on top of these plants of any concern? They can't start new plants from that can they? Another question is, do the rhizomes grow deep enough to be of any concern to things like underground pipes? So the biggest question I want to ask is, is this plant harder to maintain than bamboo or is it basically about the same?

This plant grows perfectly fine here and has for several years in the ground, that is. It just gets it's top growth killed back in the winter time but comes back up in the summer but it's roots (rhizomes) survive without any mulch or anything. I know plants usually lose a little cold hardiness in planters so I was wondering if that would affect them here. I live in zone 6b Tennessee according to the 2012 USDA hardiness zone map, but if you average up more recent years coldest temperatures, we are more like a 7a. So I guess you could say we are a warm 6b or a cold 7a here due to our elevation. We are a little cooler in the summer and little colder in winter than surrounding areas of lower elevation.

Edited May 15, 2023 by maskedmole

[Silas_Sancona]

8 minutes ago, maskedmole said:

The person I got it from simply just mows it and I don't think they do anything else

If it is A. donax, i can't see how they could mow it w/ out heavy equipment.. The stuff is HIGHLY invasive, esp. here in the Southwest / great Basin ( Where it can survive ) and California and tough to eradicate w/out a lot of effort and persistence.  ..And yes, the flower / seed " plumes " will start new plants when the wind disperses seed.

 Pretty sure there is a native " Giant Reed " there which is not invasive / ecologically damaging and looks good too.. 

As far as spreading through barriers.. can't answer that since most of the stands of it i grew up around in CA. were located along Creeks / River banks.  Does spread over quite a distance over time though.

[PalmTreesAreCoolYes]

31 minutes ago, Silas_Sancona said:

If it is A. donax, i can't see how they could mow it w/ out heavy equipment.. The stuff is HIGHLY invasive, esp. here in the Southwest / great Basin ( Where it can survive ) and California and tough to eradicate w/out a lot of effort and persistence.  ..And yes, the flower / seed " plumes " will start new plants when the wind disperses seed.

 Pretty sure there is a native " Giant Reed " there which is not invasive / ecologically damaging and looks good too.. 

As far as spreading through barriers.. can't answer that since most of the stands of it i grew up around in CA. were located along Creeks / River banks.  Does spread over quite a distance over time though.

Well, maybe they mow it in spring or early summer when the shoots are first coming up when the shoots are much softer (I'm assuming). Or they use tree cutters to cut any unwanted canes out. Or maybe they do dig around and rhizome prune it a bit. I just know they keep it contained rather well to a small area next to their driveway and it doesn't seem like they put in much effort to contain it there. They are not really avid gardening type people.

I think the compression and gravel of the driveway keep it from growing there and the shade on the other side helps in keeping it from spreading to the other side. I know this plant loves the sun and hates growing in shade as I tried to plant a little arundo donax plant in the shade one time and it sulked for awhile and ended up dying but it really flourishes in the sun. That's a real shame that the plumes on top help in spreading. Do you think I could just cut the flower plumes off when they form and throw them away or will it have dispersed in the wind by then? Maybe I could cut the flowers before they open up?

And when you say there is a native "giant reed" here, are you talking about the bamboo species that is native to here? (arundinaria gigantea)

Edited May 15, 2023 by maskedmole

[Silas_Sancona]

2 minutes ago, maskedmole said:

Well, I think they might mow it in spring or early summer when the shoots are first coming up when the shoots are much softer. Or they use tree cutters to cut any unwanted canes out. Or maybe they do dig around and rhizome prune it a bit. I just know they keep it contained rather well to a small area next to their driveway and it doesn't seem like they put in much effort to contain it there. They are not really avid gardening type people.

I think the compression and gravel of the driveway keep it from growing there and the shade on the other side helps in keeping it from spreading to the other side. I know this plant loves the sun and hates growing in shade as I tried to plant a little arundo donax plant in the shade one time and it sulked for awhile and ended up dying but it really flourishes in the sun. That's a real shame that the plumes on top help in spreading. Do you think I could just cut the flower plumes off when they come and throw it away or will it have dispersed in the wind by then?

And when you say there is a native "giant reed" here, are you talking about the bamboo species that is native to here? (Arundinaria)

Pretty sure that's it..

As far as A. donax,  totally possible the driveway keeps it in line / from going crazy, but not 100% certain. I have seen clumps where it looked like some of the Rhizomes had sneaked under paved walkways, so..  

You could definitely cut the plumes off before they go to seed ..but that's a lot of work, lol.  In CA, while it does better where it gets as much sun as possible, plenty of it growing in shadier situations under tree canopy along waterways there / here in AZ as well..

Boyce Thomposn ( Botanical Garden here ) has a patch of the variegated form ( No idea if ..or how much " tamer" it might be, compared to the standard form ) growing under tree canopy.

True, cutting down un-wanted stems when they first start sprouting would be much easier than tackling mature Canes. In CA. the " Cut canes w / tree loppers/ Tree Saw,  then treat the stumps w/ something  ..or just yank out " w/ a Backhoe method is one way they've been gaining control of it. There is also a Beetle ( ..or two?? ) that dines on the canes, ..which has also helped in controlling it.

Two snippets from the wiki page on iNaturalist discussing it's invasive potential / damage it causes:





 

[Chester B]

I've had it for three years, for me it's been carefree.  Nowhere near as vigorous as bamboo and I wish it would actually get bigger.  I can't seem to get a good patch going, right now I see only 6 stems coming back from winter.  I do grow the variegated kind.  My dad also grows it in Zone 6B in Fort Erie, Ontario.  His did get big, but not huge by any means.  Two winters back they had a cold spell that really knocked it back so it came back smaller in spring. Mine has never flowered either, so for me it's definitely an underperforming plant, but I get no summer rain, so I'm sure that's what is holding it back.