Rhizomes grow earlier than I thought!

[Alan_L]

I had the impression that rhizome growth on the runners started later in the summer, after shooting was over. Apparently, it's going on already in mid-May.

Here's my Phy. glauca 'Yunzhu'. Was planted in the Fall. Put out 2 shoots this year (just a week or two ago), but now has decided that it needs shoots more than rhizomes:



That's 3 rhizomes turning into shoots, and there's one other rhizome that has decided to stay a rhizome (you can just barely see the horizontal whitish rhizome between the left and center "shoots" -- I pulled the mulch back to reveal it).

I also see rhizome tips emerging on my Semiarundinaria okuboi, had a Bashania fargesii rhizome escape a pot drainage hole already, and one trying to on my Semi. yashadake 'Kimmei'.

So if rhizomes don't really get going until later this summer, I think I'm in trouble.

[needmore]

I saw new rhizome on one of my Parvifolia yesterday, and it is still pushing new shoots. Planted on a slope it poked out on its way downhill.

[foxd]

Brad, has your parvifolia pushed up a lot of shoots this year?

[stevelau1911]

Are you sure those are rhizomes turning in to shoots? All 4 of my parvifolia new shoots are coming up at an angle just like how yours looks. I don't think rhizomes are supposed to start growing until later on when most of the shoots are done elongating.

I think parvifolia is a pretty decent shoot producer, but unlike aerosulcata that makes one big wave at the same time, parvifolia for me likes to spread out its shooting season so I expect to get more than the 4 I have so far.

[Alan_L]

Checked this morning and there's a 4th rhizome/shoot.

Are you sure those are rhizomes turning in to shoots?

I'm not 100% sure, but I think so. Would appreciate to hear what people think: true shoots, or rhizomes turning into shoots? How can I tell for sure without digging things up? Does glauca 'Yunzhu' shoot all at once, or spread things out a bit?

I don't think rhizomes are supposed to start growing until later on when most of the shoots are done elongating.

That's what I thought too, but not anymore. This is my first shooting season with runners in-ground, so I'm learning a lot.

[stevelau1911]

rhizome culms usually have shorter, more tightly packed internodes and leaf out more than regular culms. They don't grow as tall either. You can also tell by seeing if it is coming out of the soil at an angle, or starting horizontal and then bending up which would be a rhizome. I don't have glauca so I don't know its shooting habits, but most juvenile bamboos will shoot all summer.

You can easily pick out the 1 culm that came from a rhizome in my moso which is right off my biggest culm from last year. I don't think moso makes leptomorph rhizomes at this stage.

But theres no way to tell to see if I have rhizomes running on my bamboos and I'm not going to waste hours digging to try and find out.

[ghmerrill]

whipshoots are pretty common in young plantings, but once they mature some, you wont see that happening.

[Alan_L]

Just an update on the rhizomes/whipshoots. Is it still called a "whipshoot" if it never turns upward and is content to just lay on top of the ground? It's at least 2' long already, with no indication that it wants to turn up.



I guess this plant will eventually learn which direction UP is, right?

[Alan_L]

Well, I don't have to make a decision about whether to bury the whipshoot that's staying along the ground or wait to see if it turns upward.

It's turning upward now.

But only after a deer or rabbit munched most of it off, which lightened it enough so the remaing 10" could turn upward. The rest of the shoots were untouched, which proves that this animal has the same gardening instincts as I do (that laying-down whipshoot bothered them as much as it did me).

[David]

I think rhizomes start growing as soon as the soil warms up. In fact, I see rhizomes arching and pushing many times before the bamboo shoots. There is no difference between a culm or a rhizome, they all have the same parts. A culm is an above ground rhizome, and a rhizome is a below ground culm.

[Alan_L]

This thing just won't stop putting out the whipshoots. Three more!



One of them (toward left side of image) is almost vertical, so may be a regular shoot, and some of the rhizomes that emerge are diving back down. Most of these whippers get their tips nibbled by rabbits.

Now I can't wait to see what it's shoots look like next year!

[stevelau1911]

My bissetii from a single bare rhizome progagation last year is generating over 20 rhizomes now at various sizes, some that are running literally on top of the soil, but not diving in or bending up to become whip-shoots. It looks like this plant is going to upsize a-lot next year as well as increase it's numbers at this rate. I'm looking forward to it.



I can consider myself lucky that there are no rabbits in my area.

I am turning maybe half of these rhizomes into whip shoots, especially the smaller ones that won't be able to hold as much energy or run as far. The thing to watch out for is to make sure the tips of the rhizomes already in the ground that I want to keep as rhizomes never surface because that entire rhizome will turn into a culm despite being underground.

[stevelau1911]

I think rhizomes start growing as soon as the soil warms up. In fact, I see rhizomes arching and pushing many times before the bamboo shoots. There is no difference between a culm or a rhizome, they all have the same parts. A culm is an above ground rhizome, and a rhizome is a below ground culm.

That seems to be holding true with rhizomes I've observed so far on the ones that grow very shallow. Rhizomes seem to grow to a given length, usually around the height of the culms, then stop growing and start rooting out the same way culms reach their full height and leaf out.
Right now I think my Bissetii has slowed down as far as rhizome growth since it started already in the middle of June so I'm assuming its charging it's rhizomes now to prepare for next year's shoots, make more rhizomes, or some fall shoots. I think the earlier rhizomes start growing, the better because that way theres more room to hold energy earlier.

I can kind of tell when a rhizome is produced because the soil in that direction usually gets a lot of tap roots that surfaces right under the mulch. Some of my boos still haven't produced a rhizome yet.

[Alan_L]

...usually around the height of the culms, then stop growing and start rooting out the same way culms reach their full height and leaf out.

This is not what I'm seeing. I yanked up a length of rhizome that was still growing, and it had roots growing at each node, except the newest 12" or so. The further back along the rhizome you looked, the roots were more developed.

So I'd say that the roots start growing right away, even while the rhizome is still growing.

Plus, I had 9' rhizomes from a plant that had 3' culms, so I wouldn't say they stop growing when they reach the height of the culms. I think there are way too many variables (species, soil type, climate, amount of water, age of plant, amount of sunlight received, etc.) to make a generalization about rhizome length.

[stevelau1911]

My rhizome running season has started for some of my bamboos as early as July, but it looks like they are finally making more progress now since new shoots have stopped coming up. These rhizomes are easier to locate than I thought because they often crack the ground, send feeder roots up to the surface and sometimes even jump out of the soil just to dive back in. It looks like either Vivax, or Dulcis has the largest rhizomes(near 3/4). They still seem to be growing in spurts where they reach a given length in about 6 weeks to either stop growing or make another growth spurt as if they were underground culms.

In order to encourage more running I water all the area where I think the rhizomes have started rooting, and pull out the grass where the rhizomes are headed to hopefully heat up the soil.