i have some mature black bamboo growing in the ground and want to propogate some to plant in containers. how is this done?
Hi karms, Black bamboo is the same as many of the 'running bamboos' it sends shoots out underground and comes up a little bit away from the parent plant. Think of it as the worlds largest grass. So the thing to do is sever a runner only after you have determined the 'baby' has enough root to sustain itself. I keep all mine contained in a sunken collar of aluminum flashing, from time to time the P. aurea has a tendancy to make a dash for freedom over the top. I usually watch the escapee and recapture it once it's roots have established themselves and 'viola', a new plant. Black I'm told is not as agressive, and not to mix my black with the golden as the golden will take over, but the temptation is there. BTW, if you do use flashing, bend or roll the top of the metal over. You can do yourself a real injury when weeding near it
Black bamboo, Phyllostachys nigra is a temperate "running" bamboo. It spreads, as Anne explained, by underground rhizomes. There are many different methods of progapating bamboo. The method you use depends on how fast you want to see mature culms. Propagation by rhizome cuttings likely will take up to 5 years to produce mature culms of good thickness. You can also layer the rhizomes. Air layering can simply be achieved by directing an airborne rhizome up through the drainage hole of a 2 gallon container filled with growing media. You can also dig up a division a distance away from the parent clump. However, if this new satellite clump is still young, you will get a division with a single culm. It will take another 2-3 years before it sends up more slums once transplanted. However, from your post, I understand that you probably want "instant" results. You can achieve this by taking a more mature division. Select a group of culms that you want. However, you will need to remember that the limited rootball when you take a division will only be able to support so much top growth. You can still have several thick culms in your potted up division provided you reduce the foliage by topping off the culms - I presume you will need to do this anyway, so the bamboo will fit the ceiling height of your house. Once you have figured out which of the clums you want, it's time to dig. And that, trust me, may turn out to be the most difficult part. A mature clump will have a root ball which is thick and tough with packed roots and rhizomes. Things get a bit easier if you select culms on the edge of the clumps. You will need a sturdy spade with a sharp edge, some old long handled loppers and an axe or a machette (if you can get your hands on an electric reciprocating saw armed with a green blade, so much the better). The idea is to dig around a good sized root ball, dividing any rhizomes that get in the way. What is a good sized root ball for a medium sized bamboo? I haven't been able to find a consistent answer to that question yet. My guesstimate is a root ball diameter which is 15 inches minimum, or 0.75 times the sum of heights (derived root ball diameter in inches, culm height in feet) of all the culms in the division, which ever is bigger. If you top off the culms, you can have a division with more clums. However, there is a minimum height limit to topping off, as you must ensure that there is enough leaf bearing branches for adequate photosynthesis. Once you have freed the division from the parent clump, pot it up immediately and water well. Bamboos do not like their roots dried out. It is advisable that for the first 1-2 seasons, that you allow the bamboo to grow on in it's container outside, with adequate sunlight and consistent watering and feeding, to establish the root system before bringing the bamboo indoors. Ideally, you should allow the bamboos to spend the summer outdoors, and winter indoors.