Needmore Bamboo Co.
 
                         
         Phyllostachys vivax - A friend once told me that Mark Twain said the composer Wagner was really much better than he sounds, which leads me to say that Vivax is really much nicer than it grows ...  Perhaps mine are not well sited and perhaps it takes several years to show the reported hardiness but my Vivax has been a disappointment. Essentially top killing even at +3F, it may hold a stray leaf bud or 2 in the average winter here but ends up looking so ratty that I cut it down each year.  My green form is in a raised bed and that may explain the poor performance.  The culms lean over to such an extreme I prune them to about 4 feet tall and grow it as a hedge. Although it leapt up in size the first couple of years it has remained under 1 inch in diameter after 5 years.

   I have a total of 5 forms of Vivax and I am really hopeful that one or more of these forms will really take off for me as I have seen large and gorgeous Vivax 'Aureocaulis' (golden culms with random green striping outside of the sulcus) , Vivax 'Huangwenzhu'  (green culms with a yellow sulcus/groove) & Vivax 'Huangwenzhu Inversa' (golden culms with a green sulcus) growing in zone 6b in the Netherlands.  These are sensational bamboos when growing well but mine are young and still unimpressive.  The 5th form I have is a small container plant at this time, Vivax 'Black Spot' (random black blotches on lower portions of culms) and I killed one in the ground already so this one will not be planted out until it gets fat in a container.

   The Vivax forms will leap up in size after a mild zone 6 winter and may approach 3 inch diameters if a couple of mild winters come in succession.  After top killing they size down quite a bit and on average they are not impressive in my garden. The 'Aureocaulis' and 'Huangwenzhu' both are showing stronger hardiness than my green form, perhaps lending some credence to my theory that the raised bed planting is not working out for the green one.  The rare/expensive but apparently stable 'Huangwenzhu Inversa' form was isolated from the very unstable 'Aureocaulis' which often reverts to 'Huangwenzhu' (see the below photo of the half green/half golden culm) my  'Huangwenzhu Inversa' top killed the only winter I've had it and is still tiny.		  
 
     
Straight Vivax - solid green culms, grown as a hedge in a raised bed
      
                   
           
                   
   
                   
        Vivax 'Huangwenzhu' - green culm, yellow sulcus        
                   
           
                   
           
                   
    The unstable Vivax 'Aureocaulis' - golden culms with random green striping, new culms are golden at sheath fall.    
                   
           
                   
           
                   
        A small Vivax 'Huangwenzhu Inversa'