"Winston" wrote in message
...
PrecisionmachinisT wrote:

(...)

Your biggest problem will probably be biological--insects, fungus and the
other various nasties.

That'd be great, because the plants will be completely enclosed for
most of their lives. I notice that insects are completely baffled
by poly sheet.


Pretty sure those nasties never got THAT memo...


Fungii, bacteria and viruses in the nutrient will be continuously
bombarded with UV-C in a stainless tub located in the base, so I'm
pretty confident that the nasties aren't going to be a problem.


That will probably be somewhat helpful

I *am* still working on ventilation of both the growth column and
the 'leaf area' to provide CO2 to the leaves and 02 to the roots.

The splash resulting from even a short drop into your nutrient tank will
dissolve plenty of oxygen in to it, and there's plenty of c02 in the
atmoshpere--likely any benefit from providing an accurately calibrated
additional percentage will be negligable...and in case you supply too much
well then put me on record as giving my condolences to your next of kin in
advance.


I don't suppose I could just pump the O2 from the leaves into the
growth column and allow the CO2 from the column into the 'leaf area'.

Could it be that simple? Hmmm.


I think you are way over-complicating things..

We've been growing green beans, peppers and tomatoes well into early winter
in our 40 ft poly greenhouse, and salad greens and the other common winter
crops basically till early spring for many years--in three 4 x8 raised beds
that are made out of stacked cinder blocks and filled with regular
dirt.....and out of all the problems that could possibly come up, mice have
probably taken the biggest toll.