On Mon, 12 May 2003 22:22:10 +0100, "Justin Thyme"
wrote:

I tried this with a similarly sized P.nigra at this time last year. I took
it out of the pot and cut it into two with a serrated breadknife. I potted
the odd pieces that came loose too and I now have 5 strong specimens. Do
water the plant well a few days before you split it and keep the daughter
plants sheltered from winds. The ideal place is in a cool greenhouse. Just
make sure that the roots have already filled the pot before you split them.
If they haven't, wait until next year. Try for some root, rhizome and shoot
on each part of the loose pieces.

I have just done this with part of our p. nigra that I have separated
from the main clump and dug out (not an easy job in itself). However,
I am not hopeful of success as I think I let the roots dry out too
much. After I had done it I looked it up on a US bamboo site and they
warned that you must NEVER let the roots dry out when dividing bamboo.

If they do all take, I would have about ten new plants, which I would
be tempted to grow on in pots, having seen what their parent had been
up to underground! (The same US bamboo site (I think - don't recall
where, but I would have found it with Google - suggested digging deep
trenches all round bamboos and filling them with concrete to restrict
the spread.)
--
Stuart Baldwin
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