Could use some greenhouse advice

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JacksonH

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Hi,

I want to grow 4 Pennywise cannabis plants in my greenhouse and I could use some advice.

I live in a forest in Southern Oregon, and where the greenhouse is situated it only gets about 4 hours of direct sunlight, from about noon until 4 PM. There are tall trees that block direct sunlight in the morning and late afternoon, and to make matters worse, just about when the plants start to flower and need more light, since the sun is lower, it is blocked by more trees. I grew 4 plants a few years ago without a greenhouse or supplemental lighting and the results were pretty disappointing. Cutting down trees is not an option.

I figure that I will supplement the direct sunlight with either Spider Farmer or ViiparSpectra LED grow lights, 1 light per plant. The greenhouse is 8 feet wide by 12 feet long and has a peak polycarbonate roof. I plan on using a 30 gallon grow bag for each plant.

Does this sound like a good idea? Any advice will be greatly appreciated.

Thank you.
 
MIGrampaUSA

MIGrampaUSA

3,732
263
Hi,

I want to grow 4 Pennywise cannabis plants in my greenhouse and I could use some advice.

I live in a forest in Southern Oregon, and where the greenhouse is situated it only gets about 4 hours of direct sunlight, from about noon until 4 PM. There are tall trees that block direct sunlight in the morning and late afternoon, and to make matters worse, just about when the plants start to flower and need more light, since the sun is lower, it is blocked by more trees. I grew 4 plants a few years ago without a greenhouse or supplemental lighting and the results were pretty disappointing. Cutting down trees is not an option.

I figure that I will supplement the direct sunlight with either Spider Farmer or ViiparSpectra LED grow lights, 1 light per plant. The greenhouse is 8 feet wide by 12 feet long and has a peak polycarbonate roof. I plan on using a 30 gallon grow bag for each plant.

Does this sound like a good idea? Any advice will be greatly appreciated.

Thank you.
How tall is the greenhouse? I hear 30 gallon bags and I'm thinking this guy is growing 20 ft tall trees.. I don't know much about Oregon weather in the fall but I do know plenty about how my greenhouse grows are in a Michigan fall if I allow vegetation up against the polycarb greenhouse panels.

My greenhouse is in full day sun. Michigan falls feature cold damp nights and many cloudy/rainy days making RH related issues a potential problem. Greenhouse "glass" collects condensation that does not burn off during the day. Any vegetation against the glass has potential to introduce bud rot ... and the humidity issues make WPM a potential problem.

Solution - control their size so they cannot touch any side walls or polycarb panels. Plenty of air flow. Filtered intake air. If you can get a handle on those variables, use the 30 gallon bags. My greenhouse is a 10' x 20' x 8' structure. I will run 8 plants. Each in a 7 gallon bag buried in the ground. A 5' to 6' tall plant is plenty big if I want to keep them out of the glass.

Edit: Other than that, the supplemental lighting is a good idea.
 
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MIGrampaUSA

MIGrampaUSA

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The greenhouse is just over 9 feet tall, side walls are 4 1/2 feet tall.
Sounds like you think that 20 gallon bags are way too big?
I do, yes. Other than that I like your idea.

Edit: Here's why. To make it work, you need to be able to control their size. If you can't control their size, then fall RH issues will be much more likely to occur. Think of growing quality not quantity.
 
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MIGrampaUSA

MIGrampaUSA

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OK, thanks for your reply.
Here's a picture from a few weeks ago of what my greenhouse looks like as we prepare for the summer run. My seedlings are very young and are still indoors.

Work In Progress 2
 
J

JacksonH

47
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That setup looks pretty good. We are allowed 4 plants per household here in Oregon. When I did my previous grow, the plants were in 20 gallon plastic planters, and as I mentioned, they didn't do that great, so I was thinking that bigger pots were better, but I might be making other problems for myself with 30 gallon pots.
 
MIGrampaUSA

MIGrampaUSA

3,732
263
I'm using fabric pots. I don't know if I specified that. I wouldn't use a plastic pot buried in the ground unless it looks like swiss cheese. Drainage is critical. Also its far from unheard of for roots to penetrate through these fabric pots.

There are many reasons that could have contributed to your issues with lack of light only being one of them. Over-watering is common and can occur even in plants directly in the ground. Once again, that's why I would focus on growing a plant of a size that fits your space. 4 plants kept 6' or under and not touching any glass or side-walls or even the ground should work well in your space. Use landscape weed barrier that allows water to drain through. Use border mulch and landscape stones if you desire, but that's really not necessary. I did that because my wife requested it.
 
SmokinJo421

SmokinJo421

315
43
Hi,

I want to grow 4 Pennywise cannabis plants in my greenhouse and I could use some advice.

I live in a forest in Southern Oregon, and where the greenhouse is situated it only gets about 4 hours of direct sunlight, from about noon until 4 PM. There are tall trees that block direct sunlight in the morning and late afternoon, and to make matters worse, just about when the plants start to flower and need more light, since the sun is lower, it is blocked by more trees. I grew 4 plants a few years ago without a greenhouse or supplemental lighting and the results were pretty disappointing. Cutting down trees is not an option.

I figure that I will supplement the direct sunlight with either Spider Farmer or ViiparSpectra LED grow lights, 1 light per plant. The greenhouse is 8 feet wide by 12 feet long and has a peak polycarbonate roof. I plan on using a 30 gallon grow bag for each plant.

Does this sound like a good idea? Any advice will be greatly appreciated.

Thank you.
Sounds like you got it!!
May want to consider an H.I.D mixed in w l.e.d for the mass & Co2 due to lack of lights!
 
SmokinJo421

SmokinJo421

315
43
I'm using fabric pots. I don't know if I specified that. I wouldn't use a plastic pot buried in the ground unless it looks like swiss cheese. Drainage is critical. Also its far from unheard of for roots to penetrate through these fabric pots.

There are many reasons that could have contributed to your issues with lack of light only being one of them. Over-watering is common and can occur even in plants directly in the ground. Once again, that's why I would focus on growing a plant of a size that fits your space. 4 plants kept 6' or under and not touching any glass or side-walls or even the ground should work well in your space. Use landscape weed barrier that allows water to drain through. Use border mulch and landscape stones if you desire, but that's really not necessary. I did that because my wife requested it.
Gramps,
This "supplemental lighting is what I was suggesting to you in your greenhouse
 
MIGrampaUSA

MIGrampaUSA

3,732
263
I've got six 4 ft shop lights in there to keep the plants at 20 hrs daylight. Once again, I moved the date though. I'm going to continue vegging until the weekend. Despite 20 hrs of light, my Tropicanna Poison F1 Fast is showing enough pre-flowers that some might think it's already flowering. The others are later finishers and aren't as advanced with the pre-flowers.

There's nothing wrong with your idea. I just don't trust my greenhouse to be a healthy environment after the first week or so of October. Like I said before, I'll be back inside by then anyway.
 
SmokinJo421

SmokinJo421

315
43
OK, thanks for your reply.
Keep in mind gramps is putting his pots in the ground wich would give you about 2 more feet of headroom.
If you do take that approach you may want to see how they did it in these YouTube videos.
I dnt have the link but can point u in the direction!!
Channel is Grow your Greens:
It's a series of cannabis related videos titled "how to get 10-15lbs per plant"
I will be using this process personally next year. I'm in 30gal elevated on pallets this year.
 
MIGrampaUSA

MIGrampaUSA

3,732
263
Mine are in 7 gallon fabric pots that are buried in the ground. It's slightly different because my roots are restricted from (easily) spreading out beyond the pot. Again, this is an attempt to control their final size. I don't want any of them over 5 ft tall to give them the room they need to stay away from the sidewalls and roof of the greenhouse. I am pursuing quality and will gladly exchange some yield for a quality finish.
 
SmokinJo421

SmokinJo421

315
43
Mine are in 7 gallon fabric pots that are buried in the ground. It's slightly different because my roots are restricted from (easily) spreading out beyond the pot. Again, this is an attempt to control their final size. I don't want any of them over 5 ft tall to give them the room they need to stay away from the sidewalls and roof of the greenhouse. I am pursuing quality and will gladly exchange some yield for a quality finish.
I was always under the impression cloth pots won't restrict growth, As the roots grow rite thru?
Guys in Cali line their holes w plastic on sides & a huge hole in bottom for drainage. But they're 400gal pots & bigger
 
MIGrampaUSA

MIGrampaUSA

3,732
263
They do eventually grow right through, but it's still a barrier which means it takes effort. It does have an impact on the final size. How much depends on a lot of factors including how easily or how much time it takes to grow through.

Next year I might line the dirt wall with flashing material and drop the fabric pot into the hole with an air gap all around it. I will only do that if my roots weren't restricted enough. I am running out places to put the dirt I remove. LoL
 
SmokinJo421

SmokinJo421

315
43
They do eventually grow right through, but it's still a barrier which means it takes effort. It does have an impact on the final size. How much depends on a lot of factors including how easily or how much time it takes to grow through.

Next year I might line the dirt wall with flashing material and drop the fabric pot into the hole with an air gap all around it. I will only do that if my roots weren't restricted enough. I am running out places to put the dirt I remove. LoL
Do you do the "air gap" currently
 
MIGrampaUSA

MIGrampaUSA

3,732
263
Not outside. Inside I use airpots on wheeled wire plant elevators so there is airflow all around them.

I expect root penetration outside. I am hoping that with the delayed start, the quick flowering of "fast" strains, and the pot adding some restriction to root growth, I will keep them out of the roof of the greenhouse. Peak is 8 ft at the top of hoop.
 
SmokinJo421

SmokinJo421

315
43
Not outside. Inside I use airpots on wheeled wire plant elevators so there is airflow all around them.

I expect root penetration outside. I am hoping that with the delayed start, the quick flowering of "fast" strains, and the pot adding some restriction to root growth, I will keep them out of the roof of the greenhouse. Peak is 8 ft at the top of hoop.
It makes a lil more sense now.
Thx 4 clarification
I wondered how you were keeping the size down w cloth pots in the ground!!
Unfortunately I dnt have a spot to put plants in the ground during veg
 
MIGrampaUSA

MIGrampaUSA

3,732
263
I forgot to say that I'm using LST to promote wide growth over heights. They are growing well, just more like a cork screw than straight up. If I struggle to keep them out of the roof, then we'll move to lining the hole with flashing material and using an air barrier next year.

P.S. Just got caught up on all my "likes." I was using my phone to answer while sitting in the greenhouse and enjoying the morning vibes with my wife and the dogs. Here's what they look like this morning.

Screenshot 20220705 100834
 
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