No-power outdoor light deprivation advice?

Outdoor Growing
#1

(for those who’ve grown outdoors using tarps for light deprivation)

my tenative plan is to cover/blackout with panda film from 4am until (sunset -12hr.)
i can’t use electricity and the climate is a hot valley basin(20’ abv sealevel), day temps can routinely exceed 105 F for half of July, consistent, sometimes-strong prevailing wind. Nightime temps mid-upper 60s. Passive ventilation: sub-surface intake duct into prevailing wind, exhaust duct up & awayyyyy. :dash:

my concern is humidity/condensation during 4-5 hrs. of morning light dep.

(very mixed crop, so i’m aware some little prisses might just have to go)

if anyone has fought this kind of fight, i’d like to hear your war stories…

thanks
c.s
:evergreen_tree:

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#2

Do you mean 4 PM? I would think they will need some light.

Plastic tarp won’t breath. You can count on problems.

Is Panda Film a breathable material. Regular Gardeners Cloth may breath better.

Is the area heavily wooded?

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#3

is there a reason you cant just let them start flowering on their own? it sounds like that will be a lot of extra work… autoflowers may be more suitable… but if you’re determined what’s your setup like? are they just in the open or do you have a greenhouse? maybe some type of breathable landscape fabric? you could put a laundry hamper (with holes) wrapped in landscape fabric or something over them

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#4

picture a box with wind blowing over it constantly, natural thermodynamics pulling cool dry ambient air in(buried in soil for conductive heat exchange), warmer moister air out, passively. (wind never stops for long here).

tarp on at 4am(middle of night, temps in 60s-70s), off at whatever current sunset is minus 12hr. plants only detect a roughly 12/12 schedule. and because i detect sunrise around 4:30, mid-summer.

if tarping at night & leaving it on & being lazy (i.e. put the tarp on at 9pm when it’s still 95F, leaving on all night) gauraunteed problem.

and i’m a fuckin unhealthy weirdo that gets up at unholy hours because of weirdo health problems.

:evergreen_tree:

6 Likes
#5

I am finding that the first and last hour of sunlight at the beginning and end of the season, in the green house, don’t seem to count with the plants. I have 4 in flower in the green house currently with the day light now over 14 1/2 hours and they are not having issues. They do behave differently in sun light.

99

Anyway, tarp with something that breaths. Plastic is sure to cause rot.

7 Likes
#6

Put the tarp on in the evening and time it so you remove it ten minutes before the sun rises each morning. So each night you need to move it over the crop a little earlier or later. Don’t worry too much about absolute darkness. Worry about the temperate climbing so rapidly in the morning. I know it can go from 38F/3C to 100F/38C+ in basically a matter a minutes.

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#7

the problem i find is that putting on a tarp before the sun goes down will kill them.
it get’s 115F here. (38N 121W) they’ll cook/rot. i can MUCH more easily manage morning temperature. so i will let nature do the cooling, darkening, get my ass up early & cover them when it’s cool & dark, uncover several hours later, a bit later each day until (whatever/mid-july)

this is good news and what i’m hoping for. i’ve heard it’s very strain-dependent. ?
edit:

…I’e always wondered if this was relevant for indoor growers seeking power-efficiency/reduction…i.e. “emulating” nature by only running the big bad Gavita or whatever for 4hrs(so they can pay that mofo’ off! ha!)…???

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#8

Just wondering if you had any luck? I’m in early planning, for next spring, and plan to hammer out at least one early season photo sensitive crop ,I’m also looking for strains that can handle or even shine in a light dep situ ,
Peace and love yeah !
Overgrow on yeah !

2 Likes
#9

Bump!
I am thinking three rebar mounted, curving pvc rods, with a garden cloth curtain tunnel on shower curtain rings and a rope pull. Beds are 4/6.

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#10

…run by a garage-door opener motor/mechanism, automatic timer, 45w solar panel, car battery.

:sunglasses:

:evergreen_tree:

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#11

Bump bump, trying to get a spring outdoor harvest in my glorified cold frame/greenhouse in MA this year. Sun charts say that I’ll be getting close to a 15 hour day when I hope to be close to harvest. Anyone around thats done this?

So far, goji og seems to be handling the cold nights ok, even as it’s been getting down close to 35F occasionally. Humidity has been easier to manage than my typical late summer outdoor humidity, so far at least.

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#12

Yep, manual light dep in 2018 & that spring-harvested weed was some of the best I’ve grown.

I was getting up at 4-4:30am & pulling a blackout cover & uncovering around 8:30-9am. It was a complete PITA :confounded: & really messed with my sleep so it’s not fun.

I would never cover them in the afternoon & always kept it breathing all night. Any sweat that DOES form will get nuked by morning & mid-day sun. Had very tiny little piece of budrot.

:evergreen_tree:

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#13

That’s encouraging:)

I’m in a cold climate so I think I’m fighting a slightly different battle. So far, night humidity is low enough that I can cover overnight w no problem, cold temps is the bigger concern for another week or so. The cover helps keep in a degree or two, maybe. I’m also dumping dehumidified air from an adjacent shed into the cold frame to help. So yea not off the grid entirely here, half n half on this project.

The plants are developing just a little slower than ones I have inside, but other than that they seem real happy.

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