Steve in France

Barriers don't need to be expensive , I traded a few plants for 150 ft of Barrier.I was enough to do the whole garden and in effect it was free. The trench method works , but every year you are cutting off the rhizomes that will give you big growth in the long run .Rhizome's power up Spring growth there main job is to store energy produced from the plant after the new growth has leafed out . So from early to mid Summer on all the heat ,Sunlight of the growing season is stored for the next Spring. With a Barrier 90% of the Rhizome is turned back at the barrier and you retain the max energy storing material. Also it takes a Rhizome of three years of age to produce the huge culms on Timber Bamboos or indeed max growth on any Phyllostachys Bamboo.So if you cut off the running rhizomes you will be cutting out a large percentage of the future grow on your Bamboo.
There is a saying about buying new Bamboo, "You are buying what's in the Pot not what is above the pot", it means the future of your plant is under the soil , the condition and extent of the rhizome is way more important than the culm growth .
Later
Steve

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