Temperatures

anything over 80F and you're gonna have issues imo
 
keep it under 80F, 76F being optimal
 
i grow DWC, my temp is 74F so my res stays a cool 68F

 

Anything between 68-86℉ or 20-30℃ is fine. Halfway being the ideal 

 

85 ish top end above that CO2 options are out there but you better be serious if you go that route.
65 low end. Someone earlier hit the range. Some strains do better in high temps. If you have an idea of what the conditions will be research the strain that thrives there.

 

The acceptable range is a good rule of thumb, but by no means acceptable if you ask me.  I would not allow them to exceed 80 degrees (unless you are implementing CO2) if I could help it.  Mine have crested to 82, but that doesn't happen often and it makes me nervous every time it does.  I don't like stressing my girls at all until the last week (then I abuse the shit out of them with no lights and super low humidity).
 
Some will handle a warm climate without an issue, but keep in mind the best wild growing strains are in the mountain regions of Afghanistan.  The days don't get much above 80 and the nights are cool.  Try to emulate that environment for your girls.  Another thing, make sure they have at least a 10 degree swing.  They wont be happy if their temps don't swing.

 

I lower my light until the top of the canopy reaches 86℉. I could choose to have the temperature lower but it would mean having the light further away and I find the closer it is the better the bud growth. While vegging it's not as important so I generally leave more room above the plants for some growth so I don't have to raise the light every day 
 
However some plants are more sensitive to the heat than others. Usually the plant will let you know when it's too hot by curling up its teeth, the serrated edge of the leaves. You really don't want this happening, it really slows growth. I have found northern lights to be particularly sensitive to the heat

 

There's always some argument around this one. I'm a "what they developed to deal with outdoors is what they want you to mirror indoors" thinker. Total darwinian selection adherent.

So to me, that always means what you CAN'T control, variations-wise, or have locked down control of in such a way you can provide one condition PERFECTLY for a given "natural area" for good outdoor growth, you make everything else match THAT...the conditions you'd find THAT condition in naturally, where our plants grow happy.

So, for instance, if you CAN maintain that perfect 70-80 temp range while providing 12/12 light (or near enough) in a balanced spectrum, you've got three components of perfect tropical conditions right there. So you do everything you can to match the rest of the conditions you'd find in the tropics.

But if, like me, temps right now are such that you have a natural range bouncing between the mid 50's and 80, dependent on light cycle...but in doing so I can give them a 20/4 lighting pattern, which is high summer just a bit north of me, with everywhere from almost 5 degrees latitude south to a full 5 degrees north being known for the quality of outdoor weed...so I let it ride on a 20/4 light cycle with those temps...they're naturally what we see...our average lows in July and August top 60...the rest of the time, lows are between 48 and 58 by monthly averages during outdoor season. Our highs almost never hit 80, even at the height of summer. So as long as they usually stay below there, I'm happy.

It's worked fine for me to do it that way, for multiple crops run 4 month veg minimum. Never had a lost or truly sick plants...over-topped, fighting to keep them short without SCROGGING or anything similar, which reduces weight of yield (thick plant mass, less light to side buds), but that's it, and that was MY fault, in how I manicured them.

Extended periods exceeding 85 without sufficient relief WILL cause the plants to "shut down". Places you get that heat tend to drop below 70 at night, and have a longer night than 6 hours. These plants are pretty hardy and adaptable, as a rule...you can grow them in the Sonoran Desert or Mojave, if you keep them watered, and mild other influences...where for a month, month and a half, they can count on every day topping 100 degrees...but every night dropping as low as 60, usually low 70's. And longer nights to get that "cooler air" (they also need more room for roots to go DEEP if in those conditions...roots have to be kept cool...2 inches below the surface, soil temps outside are generally 12-15 degrees colder than the average on the surface. Go 2 feet down, the soil sits in the neighborhood of 50 degrees...constantly. Almost anywhere.

At the same time...if the plants aren't getting UP to near 70 for a while pretty much every day, even if you keep them from dropping below 60, but they drop TO 60 every night, they'll have trouble during prime vegging periods. Extended periods where there are long periods in the 50's without highs in the mid to upper 60's daily harms young plants.

Basically, we've SEEN they can thrive where an individual plant experiences ranges of the low 50's to the triple digits as long as they get regular relief from the extremes.

Now, if you're an idealist, you're shooting for tropical temp ranges, soil balances, humidities, etcetera. But the plants will HANDLE much worse than that, and are still capable of producing some damn good bud in decent weights if you match conditions. Don't let it get too far beyond tolerance, and don't let extremes stand for too long...and figure your "extremes" based on what you have difficulty controlling or no ability to control at all.

 

What are the ideal ranges for humidity? And what good ways can you increase or decrease it?


Sent from my iPhone using Grasscity Forum