this may be helpful...
#817
higher rh (relative humidity) means there is greater water vapor pressure exerted on the outside of the leaves. this makes it more difficult for the transpiration process to take place, as the pressure gradient that needs to be overcome to expel internal water is higher....
also, calcium, which is primarily immobile, moves w/ water in the xylem, to the tops of plants... or other portions that water goes. when the vapor pressure deficit is low (high rh), this may decrease the flow of water & thus the limited mobility of calcium...
this is why *mistress* post over/over/over to feed calcium separate. along w/ cal's desire to precipitate when mixed w/ sulfates, phosphates....
the stomata open & close a few tymes during the day. they close during the mid-day, or hottest part of the "lites on" period... to conserve water...
the graph of opening/closing is not linear, but can be manipulated by the gardener
lots of air flow help w/ water release of plant, as the vapor is carried away, by wind...
ideally, if dehumidify, the garden can release approx. 3/4 of the water provided in 24hr...
example: if feed 10 gals of water, the dehuey/ac drain should be filled to 7-8 gals in 24-36hrs... this is the garden cycling thru the water present...
when this occur, it means that there is less actual water in the nutrient solution & greater concentration of fertilizers. & higher ph... why water add-backs (ph adjusted to acid 5.0-5.5, are maybe good)....
too much c02 during the first 1-2 hrs of lites on may also delay the opening of the stomata...
stomata can also be influenced to open/close by ambient air temps, actual leaf temps & air velocity, over canopy...
plants require far more actual pure water than fertilizers - and just as much oxygen... approx. 45% water, 45% oxygen, 5% hydrogen, 5% accumulated fertilizers (3.5% npk-ca-mg-s, 1.5% micronutrients)... so, it would seem they require just as much air as water... why some planties can be over-watered...
transpiration helps trans-port some ions, keeps the plant cooler, & maintains turgor pressure... during late flower, increasing fertilizer concentration creates slightly higher water-stress (as less is available in water filled w/ dissolved solids), but creates denser fruit, w/ more dry fruit matter.
hope this helps.
#817
higher rh (relative humidity) means there is greater water vapor pressure exerted on the outside of the leaves. this makes it more difficult for the transpiration process to take place, as the pressure gradient that needs to be overcome to expel internal water is higher....
also, calcium, which is primarily immobile, moves w/ water in the xylem, to the tops of plants... or other portions that water goes. when the vapor pressure deficit is low (high rh), this may decrease the flow of water & thus the limited mobility of calcium...
this is why *mistress* post over/over/over to feed calcium separate. along w/ cal's desire to precipitate when mixed w/ sulfates, phosphates....
the stomata open & close a few tymes during the day. they close during the mid-day, or hottest part of the "lites on" period... to conserve water...
the graph of opening/closing is not linear, but can be manipulated by the gardener
lots of air flow help w/ water release of plant, as the vapor is carried away, by wind...
ideally, if dehumidify, the garden can release approx. 3/4 of the water provided in 24hr...
example: if feed 10 gals of water, the dehuey/ac drain should be filled to 7-8 gals in 24-36hrs... this is the garden cycling thru the water present...
when this occur, it means that there is less actual water in the nutrient solution & greater concentration of fertilizers. & higher ph... why water add-backs (ph adjusted to acid 5.0-5.5, are maybe good)....
too much c02 during the first 1-2 hrs of lites on may also delay the opening of the stomata...
stomata can also be influenced to open/close by ambient air temps, actual leaf temps & air velocity, over canopy...
plants require far more actual pure water than fertilizers - and just as much oxygen... approx. 45% water, 45% oxygen, 5% hydrogen, 5% accumulated fertilizers (3.5% npk-ca-mg-s, 1.5% micronutrients)... so, it would seem they require just as much air as water... why some planties can be over-watered...
transpiration helps trans-port some ions, keeps the plant cooler, & maintains turgor pressure... during late flower, increasing fertilizer concentration creates slightly higher water-stress (as less is available in water filled w/ dissolved solids), but creates denser fruit, w/ more dry fruit matter.
hope this helps.