How to get rid of running bamboo from a garden?
Unfortunately, this is one of the most frequently asked questions. This is due to planting invasive running bamboo in an inappropriate setting with no rhizome barrier. Eradicating one of these groves is very difficult. The key to success is knowing that a grove is a single organism. It is all connected underground by a network of rhizomes. The culms (canes) are just the visible part. Chopping a section of it down will not stop the spread. It still has the whole of the rest of the grove to feed its spread next shooting season. So it will come back. The only way is to sever the rhizomes in the area you want to clear from the rest of the grove and deal with that isolated piece. Or deal with the whole grove, which is fine if it is all on your property, but groves usually straddle different properties.
There are four methods:
- Dig it up, rhizomes and all. This is undoubtedly the quickest method, but, as anyone who has tried to dig up even a small section of a single rhizome will tell you, bloody difficult. The easiest (and most expensive) way is to use a small bulldozer, bobcat excavator etc. This is only possible if there is access to the grove. Cut down all the culms (use them to make furniture!) and then dig down to the depth of the rhizomes. These will normally be found in the top 25cm of soil, sometimes shallower, rarely deeper. Remove every last piece if rhizome, but don't worry about the roots as they can't propagate. If you can't use an excavator use anything you find works - spades, crowbars, machetes, levers, chainsaws with an old chain, grappling hooks and a ute, whatever! Do not use a rotovator as it will only cut up the rhizomes into small pieces and leave them in the ground, each piece being a potential new grove!!
- Cut down the grove. Water and fertilize, then cut down the new growth again. It may shoot again immediately if you do this in Spring, if not it will shoot the following Spring. In either case the idea is to exhaust the rhizomes, by forcing them to use all their energy on the new shoots and not allowing any photosynthesis to occur to restock them. Eventually the grove will die, but it might take two or three seasons.
- The next method uses Roundup and I don't like it and won't use it but I include it here for the sake of completeness. Apparently when a culm is cut, the sap flowing through it is drawn down into the rhizomes, so painting the stump with neat Roundup is supposed to kill it. I doubt the effectiveness of this method, but i have seen it repeated in a couple of places. Once again the rhizomes will probably send up new shoots the following spring, so this must be repeated. Spraying the culm and/or leaves is useless as it will not get down into the rhizomes. And you'll have to chop it all down and remove it anyway, so you may as well just skip the poison bit of it.
- Send in the pigs!! This is my favorite method. Pigs will do a good job of eating anything, and this applies to rhizomes buried in the soil, once they've eaten everything else. They'll root around, till up the soil and fertilize it, all in one go. Admittedly, this is not a very practical method in a suburban environment.
Note Well: The second and third methods will be futile if applied to only one part of a grove and no attempt is made to isolate it from the rest, by severing the rhizomes and installing a barrier. The barrier must be able to withstand the force of rhizomes which can worm their way into any tiny crack and push its way though concrete.
Run/Clump
- Running bamboo has roots that run, with little bamboo plantlets forming all along the running roots.
- Clumping bamboo roots are just roots no plantlets are formed on the roots. The shoots that eventually form a new culm (cane) are formed close to the body of the parent plant.
- Yes, seeds can be bought. However bamboo does not flower for long periods of time (65-120 years). Different species flower at different times when they do flower, and when a species does flower it does so world wide over a several years period of time.
- MOSO (phyllostachys edulis - I don't know of anywhere that has Moso seeds in NZ. Moso hasn't flowered for years here and I don't think it is expected to either
Swampy area
Although bamboo generally does not thrive in dry climates, neither does it tolerate swampy ground very well. It appreciates moisture but with good drainage. However, bamboo planted in well drained ground near the edge of a swamp or waterway can thrive and sometimes utilize enough moisture once it develops, to dry out a swampy or seasonally marshy area. Also there are some bamboos with built in air channels in their rhizomes that allow them to be somewhat more tolerant of saturated ground. Among the species known for this are some of the Phyllostachys, for example the species atrovaginata and heteroclada. These have been sometimes planted in boggy ground near Dargaville, but have not grown nearly as vigorously as in well-drained ground.