Fired Up, Ready to Grow 3

Thanks @Hellraiser! I was reading your journal–amazing how-to guide!

Question on RH. Many guides/growers say RH should be >=60 during early veg, but I see you do fine at 40. Is that because you (seem to) keep your temp lower? I’m thinking I should ditch the humidifier unless RH falls below 40. Trying to regulate my temp to stay low 80s. Thoughts?

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@Mr_Wormwood agree about @Hellraiser! Reading his Gorilla Glue journal, trying to absorb his brain…


Just like the rest of us are… Good luck @Naptown


Higher levels of humidity is just not needed and over played. My indoor plants grew fine even when I grew in the high 20’s RH range, though I prefer closer to 40. I grew outdoors for 40 years in the southwest desert with humidity around 15-17RH (and over 100F degrees for most of summer) and they grew just fine as well, though they need more water.

Cannabis in the wild doesn’t grow in swamps or rain forests, most are growing in dry arid conditions.

Most new growers would be better off not trying to have high humidity or follow VPD charts as high humidity can cause way worse problems than low humidity, such as powdery mildew, mold, and the worst one bud rot, stuff you’ll never see at lower humidity.

See what a hemp/cannabis research scientist (Dr Bruce Bugbee) has to say about humidity, in summary he says 40-60RH is fine and don’t go over 70RH, also lots of other good info in his videos.


Here’s his video, you can jump to 12:30 to get to where he starts talking about humidity but the whole video is worth watching (a few times even).


Week 2.5 for auto GG which I’ve been overwatering. Gave her 8 oz water, no nutes, yesterday and topsoil is still wet–oops. Taking @Hellraiser’s advice to stop the droop

6 day old Bruce Banner (auto) and Harlequin (photo) doing fine.

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@Hellraiser goddamm your my hero.

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Yep, last grow I was following advice to keep VPD in green zone so RH about 70 at this point. Bought an in-tent humidifier, figured my house was just unusually dry. I’m going to follow your advice this time around. Thank you so much!

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Lol bugbee is the most scientist-looking scientist I’ve ever seen…next to Einstein :laughing: :rofl: :joy:

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Yeah following VPD can be a gamble, they say if you stick with ideal VPD that you’ll get the best growth and yield. So for a possible 5-10% faster growth and yield you risk losing a good amount of your crop to bud rot or have to deal with powdery mildew, not worth it. I’ll keep all of my buds and not risk it. I’ve never had bud rot indoors or outdoors, I’ve seen plenty of growers chasing VPD that have got bud rot, even experienced growers chasing that elusive few percent of extra yield by sticking with VPD when they don’t have the proper equipment to do it right.

It’s not that VPD is wrong, it’s just not for most home growers. VPD is fine for commerclal/pro growers with all the right equipment in a sealed grow room, air snipers/purifiers to remove mold spores from the air, dehumidifiers to make sure RH doesn’t climb too high, AC to keep temps perfect, added CO2 to make use of the extra humidity, all the controls needed to keep the environment safe to run at higher humidity levels.

Also, I would never put a humidifier in the tent, all that moisture is not good for your light, fans, carbon filter, etc…

Only time I use a humidifier is when I’m drying my harvest, to keep RH at 60 for a nice slow dry, even then it’s not in the tent (I dry in a tent), it’s in the room the tent is in and drawing air from.


Good advice again. Ty, will take the humidifier out.

GG Auto 3 week update - transplanted this morning to 5 gal fabric pot with bottom third FFOF, middle third 50-50 mix of OF and HF, top third all HF.

Following @Hellraiser’s advice on limiting water and not obsessively worrying about VPD really paid off. Removed the vaporizer from tent and just have it running in the room, keeping RH between 40-50, no where near as high as VPD charts would suggest. Temp ranges 75 - 88, trying to keep it low 80s.

Here she is pre-transplant, good color but droopy:

About an hour after transplant with 8 oz water + 1/2 tsp calmag, 8.6 pH:

6hrs later, minimal droop, looks very healthy and happy!

Bruce Banner auto and Harlequin photo, both 2 weeks. I put just enough CalMag–a few drops–to get water to 6.8 pH, then give each 6 oz when dry, every 2-3 days.

Much thanks to everyone who has weighed in so far. Happy growing!


Nice, plants are looking much better!


Little help please! My almost 4 wk auto gorilla glue’s leaves are droopy, new leaves seem to turn canoe-shape. Watering every 2-3 days after she’s dry, every other time adding tiny amount of FF nutes or calmag to get pH down to 6.5 - 6.7. Did LST (for 1st time–yikes!) 48 hrs ago.
Before LST:

Right after LST:

Week 4 for the auto GG. @Hellraiser @Dennis62 @Graysin @Mr_Wormwood (and anyone else!), any thoughts on persistent droopiness? Also, new growth seems yellow and a bit shriveled. My newbie tendency makes me ask if it is not enough of something—nutes, light, water—when it is probably too much. Yesterday’s pix, 48 hrs after LST, which I did just on the main branch (should I keep going with it?):


3 weeks in on the auto Bruce Banner and photo Harlequin. They’ve been super easy so far, looking great 5 days post transplant (deets of FF soil mix: top third is happy frog; middle third 50/50 HF and Ocean Forest mix; bottom third all OF):

Thanks as always, happy Monday!

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I’m thinking it may be PH related, but wait for more experienced eyes than mine to chime in.

The LST looks good. I’d keep on track with whatever your plans were for it for the LST.

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pH is my first thought. Need to know your runoff or preferably slurry test numbers

I will go with the above opinions as I honestly don’t know and don’t want to tell you the wrong thing

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Yeah it does kinda have that look where the ph may be off, also see a lot of white dots on leaves which may be signs of pests.

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Did 2 slurry tests. 1st with bottled distilled water, then with PureWater filter, which is my regular water source.
Distilled water mixed with soil 1:1 + 15 mins = 5.7 pH
Pure water, 8.0 pH, mixed with 1:1 soil + 25 mins (Oops. Smoked. Truth.) = 5.5 pH

One thing even I remember from scientific method is to change only one variable at a time when you’re trying to determine the cause of something. So I’m starting with overwatering as likely cause of 1 problem: the droops. I’ve been keeping both my temp and RH lower in the last week, it shouldn’t surprise me that she’s not as thirsty. She feels light to me—last feeding 55 hours ago—but stuck an old 3:1 meter from under hellraiser’s bed (see what I did there? Lol) and found some moisture toward the bottom. So, no watering until COMPLETELY dry, and I’m not going to stress with more LST until she looks much better.
Morning pics:

6 hours later:

I don’t see critters but this concerns me, the leaves dead center:

I just ordered Neem oil, should arrive tomorrow. Also ordered pH Up and Dowm.

Please continue to give me advice. 3rd time has to be the charm, right?


Sounds like your PH is too low. :rofl:

She’s not as thirsty because she can’t make the best use of what you’re giving her. You can always water to runoff with the higher PH water and see if you can’t encourage that ph to scoot up some.