"Cat(h)" wrote:
I planted some last week end, my first time attempting to grow them.
I got them about 30 cm tall from my local garden centre, and thought:
"why not" (I love jerusalem artichokes). There was about 3-4 of them
in one pot measuring about 15cm across. I figured I should separate
them and plant them individually, but did not dare disturb the very
entangled rootball/rhyzome, so planted the entire contents of the pot
in a single hole.
Should I have separated them, and if so, is it still time for me to do
so? They look quite healthy and are growing happily in my cabbage
patch, or so it seems. However, will their all being in one tight
location impact on tuber production?

In my (slightly limited but highly frustrated!) experience of jerusalem
artichokes, there is absolutely nothing short of nuking them from orbit that
will upset them or affect their production.

Not only did i dig up all tubers and all bits of tuber and then riddle the
soil the year before last, they /still/ grew an entire patch of the damned
things!! Through and around weed blanket!!!
(the boys dug through them and made a 'den' inside it, which at least made
the patch a little bit productive)