It depends a lot on the size and kind of bamboo that you have.

From your posted information, I would just repot it in a larger pot, one that is at least twice the size of the present pot.

A photo would also help.

Kt

It's a Ph. nigra in a 1-gallon pot. Here's a pic of it:

I don't think it's rootbound yet, but I would put it in larger pot anyway.

I have three or four p. nigras in pots and they have been in the same pots for a few years. One is about the same size pot as the one in your photo. I keep it in a dish of water since it 'drinks' so much each day.

When they get really rootbound, you will see water run out of the bottom holes almost immediately after or as you water it.

The rhizomes will circle around and round the inside of the pot looking for space to grow.

In a 12 inch wide pot, p. nigra will get about 8 feet tall here.

Kt

I didn't measure the pot, but I know it's a 1 gallon nursery pot. Water comes out when I water it so in the beginning I thought the potting mix is a good one - well draining, not keeping the water to become muddy. Then, when I tried to measure the moisture with the meter, it didn't go inside the soil, I always have to try different spots and it hardly goes in, and a few days ago I hit something close to the surface and when I looked, it was something like a rhizome, white-ish, long, hard, and the moisture meter couldn't get past it.

Would it be good to pot it in cactus-palm potting mix? I want to get some cor for my plumies and I was wondering if it would be good for the bamboo too. Maybe mixed with something else?

I'd wish I have a 8 feet bamboo, especially P. nigra, but I don't think we'll get it that big until next summer. :)

Mima

I used a mixture of 'cactus potting soil' with native soil here on a few bamboos a few years ago, and they all did fine.

It depends on the type of cactus-palm potting soil. I generally mix all my potting soils with soil from the ground here.

I can't speak for the potting mix you have without knowing more about it but it should be fine as bamboo grows in a wide variety of soils, especially p. nigra which likes heavy soils also.

Kt

I got the advice of using well draining potting mix, that's why I was looking for cactus/palm mix. So you say I should use a heavier soil then?

Here's the one I've found.

Thank you.

Mima

Here is a link that might be useful: Cactus/Palm Potting Mix

This post was edited by SagoLover on Fri, Sep 20, 13 at 19:19

And I was thinking to add some compost too. Would this help?

Mima

Here is a link that might be useful: Compost

Mima-
Don't be too concerned about soil...anything decent will do. Also, based on the photos you provided, you are not going to have an 8' tall bamboo next year regardless of how much you baby it. Taller growth will only come from new culms, and next year's growth will be highly unlikely to jump that much in size.

You're right. So you think maybe I should leave it as is now, in this small pot until spring?

There's no harm in repotting and it might help. Just don't have super high growth expectations from plants that size in the short term.

Of course I don't expect it to jump to the ceiling. :)
Thanks for the advice!

Mima

I wasn't sure how serious you were about your previous statement of not expecting it to hit 8 feet until next summer...

C'mon, of course I was kidding! Who's going to expect a bamboo to just explode in a few months? I know how they grow, only from new culms, meaning the current ones will stay this size from now on. I hope I didn't sound mean or anything, I was just kidding around here. I know I appreciate all your advice given here. It actually helped me tremendously, and thank you again for it!

Mima

Here's the nigra potted up yesterday:

And its roots after removing it off its old pot:

I've had bamboo that was more rootbbound than that, but I think you made the right choice and repotted it.

It should be good for a while in that pot. A 10 gallon, or larger pot, would be even better.

Kt

Ahhh, now you tell me?? Jk. I think it will stay in the 2 gallon for next year and then repot it next Fall maybe.

Now, one question: if the pot is too big for the plant, wouldn't the soil mix hold too much moisture because there are no roots all the way to the sides or bottom to drink the water, therefore keeping too much unneeded moisture to the actual roots?

Mima

If the soil drains ok, there it's no issue. Think about bamboo in the ground...which doesn't fill all the earth around it.

That's true. I was projecting what I know from other plants, and even for those that too-big-holding-moisture kind of thing might be a trait of the over-protective growers, which I'm trying not to be.

Thanks for the input.

Mima

Mima-
Bamboo is a plant that is pretty tolerant of moisture conditions. As long as you don't let it dry out completely, or have the roots submerged in standing water for a couple of weeks, it should be fine.

Thanks kudzu, I will treat it then like my other plants that have similar requirements. :)

I wanted to ask something and I forgot: the rhizome that can be seen in the soil when removed from the pot, wasn't it supposed to be whiter/lighter in color? Is it something wrong with it?

Thank you.