Hi Iris >Then as the > weather warms up and more outside air is allowed in, root growth starts up > again. > >This is the old fallacy of post hoc, ergo propter hoc.
Well Latin not being my forte, I have very little idea what that was all about so will make no comment. >You have no comparison >to know exactly what causes the plant growth to slow down. You have not >controlled for temperature, light, daylength, & other factors. I have not 'controlled' for anything. I am a hobby grower and I do quite nicely if I do say so myself, despite not controlling for anything. What I am saying is that my observation over the last 15 years of growing orchids in the same hothouse, is that when winter comes and the temps drop, I close the house off for most of the day to keep out the cold. Sometimes it is closed all day if the outside weather is really cold. It would seem to me that in these circumstances it would be only natural that the green stuff in the hothouse would use up all/some/lots of the available CO2. Spring arrives and a number of things happen. None of which are 'controlled' for. There is more light. There is more heat. The days get longer. This allows me to let in more air from outside which is now not cold. Indeed the swamp cooler cuts in and blasts away for hours. Comparing this situation to the previous situation during the depths of winter, it is no surprise that growth start again in some orchids. During the winter, the house is kept at a min 15C and some shadecloth is removed to let in more light, but the one factor that I can't do much about is the resultant drop in CO2. The same must be happening to many orchid growers around the world. Charles E. Bracker must be suffering from the same problem in his closed off basement (?) rooms. Hence our attempts to increase the CO2 in our respective growing areas. Iris, if you are looking for scientific proof, you will have to talk to scientists. Most of us work on the basis of 'if it works, it works'. Not very scientific but the best we can do. >CO2 must have some effect. I breathe on my orchids every day, and some of >them bloom. >Iris I hope you are controlling for your breath. Is that two breaths per orchid? Or three? I breath on mine too and have a good percentage that bloom during the winter. Even so I feel sure (how un-scientific is it to 'feel') that additional CO2 during the winter would result in even better flowering. Happy growing Tony _______________________________________________ the OrchidGuide Digest (OGD) [email protected] http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
