How cold does it normally get over there?

If it gets to freezing or below, I would bring in the Lako, Asper, and maybe the Oldhamii.

I put my frost sensitive bamboos inside of a greenhouse if there is a threat of frost, and then remove them as it warms up, and that is not easy when some of the pots weigh up to 100 pounds and the bamboo is over 24 feet tall.

Kt

Sometimes it does get to freezing, but it is not usually for more than a few hours, hardly much below 32* and rarely two nights in a row. I do not have a greenhouse, but I have nothing against bringing them in the house. Should I put them on heat or under lights? Or do you think natural light through slider would be enough.
Kentuck, what do you have potted that is 24 feet? What size is the pot?

Thanks for the info!

Are you planning on leaving them inside for the length of the Winter, or just on nights when it gets cold?

If you put them where it is warm, they will tend to keep growing, and will need good lighting. If they are inside for only a day or so, it won't hurt them to be without direct sunlight.

I don't have very good luck keeping potted bamboo inside heated areas, unless they get very good light, some direct sunlight if possible. Inside of my greenhouses, which I heat only on nights that drop below 30F(which happens on the average about 6 times each Winter), the bamboo, for the most part, become dormant and stall their growth unless there are several days of above normal temps where the inside of the greenhouse gets very warm, then the bamboo tends to come to life and start growing.

Look in the gallery under the title "Oldhamii, One Year Later..." that I posted a while back. Those Oldhamii are 24 feet tall not including the pots. The pot on the left is a green 14-inch pot from Walmart. Not pictured, is my G. atroviolacea which is in a larger pot, and when it is saturated after watering, it weighs over 90 pounds.

Kt

Hey Kentuck! I was thinking that I was only going to bring them in when there was threat of frost.
There is direct sunlight in the spot I had planned on putting them. Will it hurt though to bring in to heated area for just a night or two and then put them back out again?
I am going to check out the gallery.
Thanks for your info!

Before I had a greenhouse(s), I would bring mine inside of my house, which had no direct sunlight or much outside light at all. It did not seem to bother them at all, going from the comfort of my warm home, to back outside in the colder temps. Of course, I did not put them back into very cold weather, it was usually in the mid to upper 40's before I put them back outside.

What do you think of the photo in the gallery??

Kt

I think that I am going to try outside and bring in when threat of frost.

Kt, photo was nice, Oldhamii was GREAT! I am hoping that my Oldhamii that I have inground looks that great in Spring. I think it will probably be a few more growing seasons before the 2 I have in pots get that size.
How old are they? Are they a clone or from seed?

They are clones. The one on the left has been in that pot, undivided, for two seasons, and needs to be divided soon. The one on the right has been in that pot for one full growing season. I usually divide them into two halves each time they get rootbound, since the culms are soooo large. Smaller bamboos in the same size pots, I would normally divide into quarters.

My in-ground Oldhamiis are massive. From a two gallon(?) pot, both had culms almost three inches thick in their second season outdoors, even after freezing back in the winter.

In your zone, I think by the end of next year, yours should, or at least could, look as large or larger. The problem with such a large boo in a small pot is keeping it watered during the hot Summers. A small pot can easily dry out, and a bamboo can die quickly so you might have to keep a close eye on it if kept in a pot. In your zone, Oldhamii should do much better than it does here in z8b.

Good Luck

Kt

Thanks for the info! I will probably pick your brain more later on as they grow about dividing, if that is OK.
Have a Great holiday!

That's no problem. Everyone here on this forum is very helpful and willing to share their growing experiences, so there are plenty of brains to pick. Feel free to ask anytime.

Merry Christmas!!

Kt