Outdoor Hydroponic Rooftop Grow - Recirculating DWC - No Airstones & No Medium!

[Crazy Chester]

15+ years says stick with 69F or your potential for issues will be significant. Considering you're outside as well, I would not even consider going outside the 65F/69F window. At the peak of flower, it only takes a few hours of not enough O2 to do extensive damage. There are many other factors at play in the study where 72F worked well.

I would use a thermostat controlled outlet with a probe in the reservoir. Set your temp at 69F and plug the aquarium heater into it. I would also look at putting it on a timer so it only comes on during the night, early morning.

Good idea to use a thermostat/timer, Douglas. I'm going to mess around a thermostat and/or timer and see if I can get my low temp of the range up a bit.

 

[Douglas.Curtis]

Calculate your time/efforts/resources. What's going to be the least amount of work, chasing temps or switching to pebbles? Which will have the least/most failure points, and which failures will have the most potential harm for the plants?

These are good questions to answer for any grower, and especially so in situations like this.

 

[Crazy Chester]

Calculate your time/efforts/resources. What's going to be the least amount of work, chasing temps or switching to pebbles? Which will have the least/most failure points, and which failures will have the most potential harm for the plants?

These are good questions to answer for any grower, and especially so in situations like this.

Good grow wisdom - those are definitely the variables I'm considering. Fortunately, I have some time to decide on the final set-up because I have to complete my gradual step down of my indoor veg light cycle for the plants that will go into the system - it won't match the light cycle outdoors until May 10.
In the meantime, I'm going to experiment with what I've got and see how the temp numbers turn out.

The plants have also been hardened off to the sun - I bring them out for a good 8 hours of direct sun a day. If they flower before I set them out I expect most of May to consist of a mild re-veg from a mild flowering - then off to the races for at least mid-June through July.

That should be all the veg I need for bountiful fall flowers.

 

[Crazy Chester]

With reservoir temps being just right with intermittent use of a heater, the sombreros I put on the tote/planter covers, mild weather in the forecast, the fact that I had stepped my mothers down to 14.5/9.5 by last night and the fact that I'm at about 14 hours, 40 minutes of daylight outdoors today - I just put my mothers outside on the roof (after cloning them a few days ago).

I haven't seen signs of flowering since my 1/2 hour a day step-down from 18/6 started about a week ago and now the girls will notice the 10 minute increase in daylight at their new outdoor location (and regular increases thereafter as the season progresses) - I'm really hoping they haven't gone into flowering mode - that would be so cool if they just take off vegging after they adjust! If not, there's plenty of time in the season for them to complete a mild re-veg in the increasing daylight hours outdoors.

So, today I put covers made out of fairly thin polycarbonate corrogated sheets. I will also put some screws in the edges of it later, a la WelderDan, so I can tie the plants down to train them.

I used this:



I cut a hole through the insulation, res cover and the corrogated polycarbonate and installed some PVC 2" to 1.5" inch adapters to place the plants' net cup into and to provide a channel through the depression in the top of the tote for the roots to go down into the nutrients.

It installed like this:





The tote/planters ended up looking like this:



Here's the plants getting used to their new sun bathed home:

 

[Douglas.Curtis]

My first thoughts from the photos were flashbacks from roofing jobs I've done in the past. How hot does it get at peak summer there, and how long does it last? You'd be amazed at how hot it can be on a tarpaper roof on a moderate 75F day in full sun. The sun on the black pipe will also generate a lot of heat in the nute solution.

 

[Crazy Chester]

Hi Douglas - yup, those shingles get pretty hot in the direct sun - even if it's not a hot day. In the shade of my sombreros the roofing feels at least 10 degrees less than the spots in the direct sunlight - right around ambient.

I used to do roofing too - in a hotter area than where I live now. I remember when temps were approaching 100 degrees I'd have to cradle the shingle by carrying it by laying it over the length of my arm to move it from the stack to where it was being nailed - otherwise it would just fall apart - it was so gooey.

But, here, it is a way less hot area of the country,

Here, it just doesn't get that hot - in May the average high temp is 66, in June it's 70, in July and August it's 71 and the hottest it gets is an average high of 73 in September.

That's part of the reason I like those sombreros - they make the area around the plant hotter than the nutrient solution. Otherwise, it's a bit too chilly for plants like tomatoes and cannabis to do really do well here.

Also, I've got my roof planters insulated on the bottom and they are on little legs, so they are not actually touching the roof. The res stays about 2 degrees less than ambient until the environment catches up to it in early evening. By the time the res gets close to ambient temps, the high temperature for the day plummets quickly and the uninsulated res ensures that it never quite gets there.

 

[Fred Sanford]

Pretty cool man. Is there wind there?

 

[Crazy Chester]

Pretty cool man. Is there wind there?

Hi Fred Sanford - welcome to the thread!

Yeah, I'm in a windy area, probably no more than 2 miles from the coast.

 

[Douglas.Curtis]

From the sound of it, you've done a great job building for that local, the cool summer temps look like a win as well. Kudos!

 

[Crazy Chester]

From the sound of it, you've done a great job building for that local, the cool summer temps look like a win as well. Kudos!

Thanks, Douglas! Yeah, the climate here really does make it fairly easy to keep hydro res temps within range outdoors. More extreme climates may require more insulation, buried reservoir, lighter colored pipe insulation, etc. But, if I were in a spot that typically had high summer temps, I would instead do a hydroton system with evaporative cooling effect - like you had mentioned. The more I think of it, the more I like that idea for hot climates...

 

[Crazy Chester]

One week after moving to their new home, the girls have shrugged off the change and put on new growth:



Fire OG:

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Super Lemon Haze:

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Capstone:

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I took some tops for clones. When I was cloning the Capstone top I smelled where I made the cut - it smelled exactly like Cap's description of the terps the finished buds are supposed to have. It was truly sweet peaches and plums and loud too! I'm excited about this Capstone - at harvest, it's going to absolutely stink of stone fruits!

In other news - I think I actually avoided these girls flowering. The pics were taken 12 days after I had started stepping their indoor light cycle down to match outdoors. I'm hopeful, because the new growth appears to be just that, rather than stretch and there's not a pistil in sight!

Man, if I sidestepped them from flowering outdoors this Spring - in Autumn, they should be some full figured ladies!

 

[Douglas.Curtis]

Awesome! Glad to hear they've not hit reveg and things are going well, truly awesome and looking good for the season so far.

I commend you on your planning and execution, good job!

 

[Crazy Chester]

Thanks, Douglas - I'm loving it!

 

[Crazy Chester]

The girls continue to grow well:



So, I took some clones before feeding them to make them grow even wider - then we had a rare May rainfall:

 

[Mars Hydro Led]

It is a grow art.

 

[Crazy Chester]

It is a grow art.

Thanks for stopping by, Mars - feel free to hang out - while the plants settle in for the summer!

 

[Crazy Chester]

Here's an update I was going to post yesterday, but didn't get to.

This is what the plants looked like yesterday morning:

 

[Oddity]

Wild! Looking forward to seeing more - they seem to be loving it on that roof.

 

[Crazy Chester]

The girls are getting bushy:



Capstone:



Super Lemon Haze:



Fire OG:



I'm going to clone them one more time, taking them down another level, then, I intend to take the best of the grow tips and train them horizontally to keep them low and wide. I envision the canopy to be maybe 7-8 feet wide at the top and tapering to around 4-5 feet wide at the bottom, kind of like an outdoor SCROG, hopefully bristling with 2 foot buds at harvest!

 

[DARKSIDER]

The girls are getting bushy:

[URL=https://www.icmag.com/ic/picture.php?albumid=83028&pictureid=2044187&thumb=1]View Image[/URL] [URL=https://www.icmag.com/ic/picture.php?albumid=83028&pictureid=2044188&thumb=1]View Image[/URL]

Capstone:

[URL=https://www.icmag.com/ic/picture.php?albumid=83028&pictureid=2044191&thumb=1]View Image[/URL]

Super Lemon Haze:

[URL=https://www.icmag.com/ic/picture.php?albumid=83028&pictureid=2044190&thumb=1]View Image[/URL]

Fire OG:

[URL=https://www.icmag.com/ic/picture.php?albumid=83028&pictureid=2044189&thumb=1]View Image[/URL]

I'm going to clone them one more time, taking them down another level, then, I intend to take the best of the grow tips and train them horizontally to keep them low and wide. I envision the canopy to be maybe 7-8 feet wide at the top and tapering to around 4-5 feet wide at the bottom, kind of like an outdoor SCROG, hopefully bristling with 2 foot buds at harvest!

Looking well more than well