do marijuana plants continue to breath co2 during the dark period?

Discussion in 'Growing Information' started by cesarhorta, Sep 30, 2007.

  1. cesarhorta

    cesarhorta Registered+

    do marijuana plants continue to breath co2 during the dark period?
    they transpire water in night? is really need to have abundant airflow in night period? this is just because i read that the plant "work" in day time is very different from the plant "work" in night time. is this true? thank you very much for the answers.
  2. ProGroWannabe

    ProGroWannabe Registered+

    Hey cesar. Yes, night time prcesses and daytime processes are quite different. I'm just now studying the use of CO2 for my own room, so I don't know a whole lot about it yet. But, what I've read so far, says that CO2 is wasted at night. In my estimation this is because it is during the "day time" or lights-on cycle that the plant executes the processes of photosynthesis. CO2 is used for photosynthesis. When the lights go out, photosynthesis stops, therefore the plant won't be ingesting the CO2 "at night".

    If anything above is wrong folks, please don't hesitate to correct me.
  3. rhizome

    rhizome Registered+

    Ya got it, PG. 'zactly.

    Plants do continue to transpire- remember also that temperature will decrease when the lights are off, which increases vapor pressure- can lead to condensation/ humidity problems.

    You really do need to have good ventilation during the dark period- anything else will eventually go to mold.
  4. ProGroWannabe

    ProGroWannabe Registered+

    Thanks rhizome! I was hoping you'd stop in on this one.
  5. growbe

    growbe Registered+

    During the propagation stage, lights should be left on as long as possible, up to 24 hours per day (big debate on this one). Strong initial growth will make the young plants healthier and more resistant to disease, ultimately providing better yields. As the plants begin to mature, however, light duration should be reduced.
    Plants use periods of darkness, too. During dark periods, plants continue to take in oxygen and give off carbon dioxide in a process called respiration. During this time, the plant uses some of the energy that was stored as sugars during photosynthesis, producing proteins, hormones and other complex products. Therefore, lighting mature plants more than seventeen and a half hours per day will not increase production significantly, since photosynthesis will slow down after a certain number of hours. Keep the fans going during the off hours and make sure your controller is set to a certain humidity and temp. and all will be fine (hopefully).

Share This Page