The Basics (Homer Simpson forehead slap) 'Duh!'


O.K. - I have been having a problem with stunted plants since I moved to the desert. Drove me nuts. Ph, PPM, perfect. Water is hard, around 400, but liveable. Growing in pure Coir. 280 watt LED. Plants looked healhty, roots healhty, but not fully developed. They were just midget plants.
I got one of those weekly Robert tips this week. I love those, because they make me pause, and think about the subject. This week - humidtiy. Robert opines that below a certain relative humidity (below 30%, or so) the plant feels like it is in danger of drying up, and the stoma close. Therefore, no transpiration. Therefore no growth, and there is no nutes traveling up from the roots.
So, until the monsoon started in July, the humidity was aroud 15-20 %. I wrongly thought that this would be good, just increase transpiration. I am now convinced this was my problem.
O.K. - you experts (you know who you are! :wink: why is it, then, that the Pansys, Marigolds, Cardinal Climbers, and so forth, that I grew outside this year seemd to thrive incredibly well. Is Cannabis from a class of plant that can’t take the low humidity? I need to know the answer to this question, to regain a peaceful mind. There are Datura here as well, that grow in Iowa, but they, too, are quite small, compared to their cousins in temerate climes. That is anecdotal evidence to support Robert’s thesis, it seems to me.
Moving to the Bay Area in Cali on October 1st, so humidity levels will be more in line with what I know from Iowa.


I read that article recently myself and found the information interesting. I myself living in the deep desert southwestern united states am always growing in very very low humidity and have not had any problems as long as the roots are getting plenty of water, but then I grow and flower almost exclusively in DWC hydro and this can add some humidity to the grow room, but I’m pretty sure I’ve grown in 10%-20% humidity without any problems. I even have a friend that guerrilla grows outdoors in the fall and harvests in the winter when it’s bone dry and grows monster huge plants. I do know high humidity during veg or flower can lead to more distance between internodes as the plant stretches more in high humidity, possibly to try and prevent bud rot.

Did you say you are growing in DWC now as well? If not, or maybe even so, I’m wondering if any sort of root growth restriction could be part of the equation as in being root bound.


Well, that must not be it, then. DWC adds a bit to the Humidity, but wouldn’t raise a room with ventilation going a significant amount. I wondered about the outdoor. I’ve seen many bud-porn pics in the desert.
How 'bout this - I burned all of them with my LED when they just had the initial, single leaf out. Could a shock at that time affect the whole rest of the grow? Seems to me the regular plants come back from nearly every malady, given time, and loving care. What could cause an underveloped root structure, even while what is there is healthy as you please?


I suppose that could be a contributor, but like you said, usually one can grow the plant in veg longer to make up for any slow growth as it recovers from any damage and usually wouldn’t see much difference in the end result.

It is curious.


A shock like that can attribute to stunted growth, and the plant will not recover to the point it gets really big all of a sudden. It is advisable to find a way to add humidity to your grow space. I would consider a humidifier. Plants in veg should be at 50-70% humidity. An average of 40% in flower.

In commercial greenhouse ops; The books tell us to start seeds and raise seedlings at a level of 75-95% RH. Take it for what it is worth, but I believe that RH very well is the contributing factor to your issues.

BTW Hey! And glad to hear from you J :slight_smile: Peace

p.s. A bucket full of water with a fan blowinf over it; JUst might help raise the RH



 All that you say is dead on the point.  I,as I assume most medical grows and hobby grows do as well, have been putting the g-room together needed item by needed item, on paydays.  It's gettin' there.  
 One last comment on my small plants.  They were six weeks from seed on Monday, when I put them in the flowerroom.  Average of 14-15 interniodes.  So they may surprise me yet with weight of bud.  I've got them opened up as much as possible (LST, Supercrop), and they are amazing little bushes.  They look like hedges.  Time will tell...

Now, for the really big news. I have set a date certain to move to San Fran. October 1st. So, in 45 days I will be in the Land of Weed. I can go into a store and legally buy colones, or bud. Growshops all over the place. My Daughter tells me that they smoke weed in bars, and parks, anywhere and everywhere. Oakland, where I am going, passed a city ordinance that anyhting to do with weed must be the very lowest priority for the Pigs. Pretty cool, no?? So, I am unbelieveably jazzed about the move.
Good to hear from you as well, my friend. Keep the shiny side up, and the greasy side down.


Good to hear. :slight_smile: I think you will end up happy with your grow; Patience and attention goes a long way. And, believe me, I know about buying piece by needed piece. Been there done that; Ooops! I still am. Just got a new 2’ T5 :smiley: