Looking to invest in a greenhouse...

MustangStudFarm

MustangStudFarm

Well-Known Member
NirvanaMesa said:
Without going into great detail, heres a few issues you will run into with a GH. Plants are generally more happy outside of greenhouses where they are in more direct contact with the weather. Plant tissue doesnt harden off as well in a GH. It tends to stay soft and get chlorotic. And it also is more weak from lack of wind. A fan blowing around is not the same as wind. Also there tend to be larger temperature swings inside a GH. its hotter during the day and then drops to outside temp at night. Unless you get some $$$ heating equipment, its not going to stay warm at night. So if you plan on growing in winter, and its frosty where you live you will need heat and lights to give more daylight. Then theres the issues of bug infestations. Much more of a problem in a GH due to fast growing plants with softer tissue. Mites, aphids, etc love a GH. And theres issues with automating the temperature and humidity controls. Without some sort of automation with fans and or cooling walls or mist systems you will surely cook your plants. It takes a lot of work to get the temps and humidity where they need to be. Trust me on this that a GH is a pandoras box. You WILL be dealing with those issues guaranteed.
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The biggest problem that I will be facing is extreme heat, it's too hot during the summer to have plants in direct sunlight for the full day. That is why I am suggesting a mini-split A/C and making it over sized, maybe a 2-3 ton. My 24,000btu Mitsubishi Mr. Slim works fine on my 1,200sqft house during the summer and I would like to think that it would work on a 400sqft greenhouse too. I'm often wrong about these things and that is why I am here. I wanted to use sunlight instead of indoor growing because I am finally legal and I don't have to hide it anymore.
 
MustangStudFarm

MustangStudFarm

Well-Known Member
NirvanaMesa said:
Unless you get some $$$ heating equipment, its not going to stay warm at night.
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I will be dealing with the opposite, heat. I'm willing to invest around $20k in the project and the greenhouse is around $13k. I'm leaving room to have concrete poured and electrical subpanels installed. I have my own A/C equipment to install mini-splits and the Mitsubishi on my house is working perfectly after 2-3yrs.
 
NirvanaMesa

NirvanaMesa

Well-Known Member
I doubt its too hot to have plants in full sun all day unless you live in AZ or the desert parts of CA. I live 16 miles inland in the hottest area of San Diego county and can grow plants in full sun on the side of a south facing hill. We even had a few days of 115F back in June. The plants dont seem to care at all. As long as they are watered they do just fine in crazy heat.

I think you will find that pretty much no one runs AC in a greenhouse. Greenhouses get way way hotter than a house as they absorb and trap all the energy from the sun. People typically use evaporative cooling walls or high pressure mist systems to cool a GH. When water goes from liquid to gas state it absorbs a huge ammount of energy. This works especially well in dry climates. If you are in CA, its going to work like a champ.

For an AC unit to work, you would need to shut all the vents on the GH. Because the air being cooled needs to be the same air recirculating. You can't have a vent or fan pulling fresh hot air in and expect to cool it with an AC. Its going to run nonstop and never cool the GH to where you need it.

Im not trying to poo poo you either. Im a commericial nurseryman and have lots of experience in this area.
 
MustangStudFarm

MustangStudFarm

Well-Known Member
NirvanaMesa said:
I doubt its too hot to have plants in full sun all day unless you live in AZ or the desert parts of CA. I live 16 miles inland in the hottest area of San Diego county and can grow plants in full sun on the side of a south facing hill. We even had a few days of 115F back in June. The plants dont seem to care at all. As long as they are watered they do just fine in crazy heat.

I think you will find that pretty much no one runs AC in a greenhouse. Greenhouses get way way hotter than a house as they absorb and trap all the energy from the sun. People typically use evaporative cooling walls or high pressure mist systems to cool a GH. When water goes from liquid to gas state it absorbs a huge ammount of energy. This works especially well in dry climates. If you are in CA, its going to work like a champ.

For an AC unit to work, you would need to shut all the vents on the GH. Because the air being cooled needs to be the same air recirculating. You can't have a vent or fan pulling fresh hot air in and expect to cool it with an AC. Its going to run nonstop and never cool the GH to where you need it.

Im not trying to poo poo you either. Im a commericial nurseryman and have lots of experience in this area.
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I listened to a podcast that said basically the same thing, wet wall with light dep cover. I wanted to get info like this before I invested.

https://www.shapingfire.com/podcast-feed/episode-41-cannabis-greenhouse-rescue-with-guest-eric-brandstad
 
NirvanaMesa

NirvanaMesa

Well-Known Member
Wet wall 100X more efficient than an AC unit. Assuming you live in a dry climate. Well, the beauty of evap cooling is you really only need it on those hot dry days. Anyway, looking at greenhousemegastore.com and farmtek.com

Those places have everything you need. You can buy the wet wall material from those places and build your own wet wall using rain gutters and a pond pump. The stuff you want to source from the store is the 3 or 4 inch thick stuff that the water flows through and air is sucked through. I forgot what its called, but its a mesh type material.
 
sensi8739

sensi8739

Well-Known Member
@NirvanaMesa Far be it for me to claim I am a GH expert, only been running one for a few years now, so take this along those lines of course... but from my experience, temperature swings can be modulated passively with shade cloth, enough air exchange and a large volume of water in barrels along your North wall. No need to go crazy with the gadgets and automation. Misting to cool adds humidity, as does a water wall, although to a lesser extent because air passes from in to out, but there is a bit of passive exchange going on as well. I always say that the more you can keep water just around the root zones and away from the rest of your greenhouse, the better off you are in terms of regulating humidity. I dunno though, I guess I'm also curious what you refer to as chlorotic/soft growth in a greenhouse? I've been doing sungolds, heirlooms, and some random stuff for a few years now and haven't run into those issues. Bugs/pathogen buildup? Absolutely. Weird growth issues? Nope... In fact, everything in the GH grows so much more lush and vivacious than my outdoor garden, and feel the exact opposite as you in terms of plant quality coming from the GH. Would you mind elaborating?
 
NirvanaMesa

NirvanaMesa

Well-Known Member
Bug infestations are a sign of soft plant tissue. Not all plants will develop chlorosis but some tend to in a GH because of the extra heat and humidity. Plants grow faster and tend to not harden off as well as if they would outside in the elements. Thats why they are bug and mildew magnets. Its not strange growh its just more soft and suseptible to attack.

As far as cooling, absolutely shade cloth and fans. Thats all I use most of the time. My fan pulls in 1.5X the volume of the GH every minute. Its a big ass fan and its on a 30$ thermostat and keeps the temps right where I want them. But when its 100F outside, pulling in hot air doesnt help. Right now its 70F outside in december and I can keep my GH around 90F inside with just a fan. During summer I have to run 50% shade and a mist system. Theres no way to passively cool your GH if the outside air is hotter than what you want the inside to be. Its always going to be hotter inside a GH than out if the sun is shining. Now if you live somewhere with mild weather then you may be able to get by without any knd of evap or other cooling other than a fan. And in that case a GH would also be extending your season and providing extra heat you need. Where if you live in southern CA like me, a GH isnt helping a lot during most of the year. We already have a very long growing season, warm dry weather etc. It becomes a pain during summer to keep the temps below 100F. Thats why I am saying its better to just grow outside sometimes. Especially if you live somewhere that can easily pull off an outdoor grow and no need a GH. Keeping your neighbors from seeing what you are growing is not a great reason to get a GH. Trying to extend your growing season or raise your temps for better growth are good reasons. Im not knocking anyone for wanting a GH to keep whats inside out of sight, Im just saying it may be more trouble than you are expecting.

I have done tomatoes in the GH in winter. They do fine. I propogate avocado trees, cherimoya trees, mango trees, dragonfruit cactus, pineapples and a few others for commercial nursery stock. Avocados do the worst in the GH. Very prone to aphid attack and chlorosis. I have to feed the trees systemic pesticide to keep the aphids under control. My GH is absolutely golden this time of year though. Im propogating stuff that would otherwise not grow outside this time of year. And I will have them ready for sale in spring. And I could probably grow great weed in there this time of year too except for the photoperiod is too short. Would need supplemental lighting to veg the plants and keep them happy on cloudy days.

If you do some digging or talk to the big pot growers in Northern CA, they will tell you they only use the GH to keep the rain off their plants or to do light dep. They will tell you the plants are healthier and less prone to issues when they can leave the cover off the GH. Now I have no idea where anyone else is located in this thread. No one mentioned what state they are in. If you guys are in a more cool climate or one with more rain, humidity etc you may have totally different experience and or set of problems. I just want people to realize when you throw down a GH, its not just automatically a perfect growing environment. Its most likely going to need some adjusting and there will probably be unforseen issues. And it will probably cost more than you were origjnally expecting to get it all sorted out.
 
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sensi8739

sensi8739

Well-Known Member
Right on. Yeah, I definitely agree that there is a large learning curve, and you absolutely will make mistakes that cost money and time to correct. I still have stuff every year I want to modify or correct.

My environment is a bit different than yours. I'm in Colorado at 7200 ft. The weather is cooler and tends to run wet from mid July through August, then starts getting cold with bouts of cold humidity in mid September through the fall. Our first frosts tend to fall around the end of September/early October. I would probably not use a greenhouse if the climate didn't require it, as you are right, the cost of cooling during the hot months would get pretty extreme if I needed much more than a fan and shade cloth to stay below 90, and would probably be worse for the plants anyways. For me though, it keeps the water off when bud formation is naturally occurring and I can run a furnace to try and keep temps above 60 when pushing into October, hopefully helping to head off mold formation during cold and wet weather events.

Greenhouses are fun though! Definitely not the easiest thing to fine tune, but as an outdoor bubble of variables you have some greater degree of control over? I dig that. It has become a bit of another hobby passion and compliments a hobby obsession with cannabis as well. I'd say, when considering if it's right for you, just be aware of what you are getting into, the costs, workload, climate considerations etc. Don't be worried about jumping in though, and don't be upset if you make some mistakes along the way! In a lot of ways it's like taking your indoor tent and working around nature.
 
7

757growin

Well-Known Member
NirvanaMesa said:
I doubt its too hot to have plants in full sun all day unless you live in AZ or the desert parts of CA. I live 16 miles inland in the hottest area of San Diego county and can grow plants in full sun on the side of a south facing hill. We even had a few days of 115F back in June. The plants dont seem to care at all. As long as they are watered they do just fine in crazy heat.

I think you will find that pretty much no one runs AC in a greenhouse. Greenhouses get way way hotter than a house as they absorb and trap all the energy from the sun. People typically use evaporative cooling walls or high pressure mist systems to cool a GH. When water goes from liquid to gas state it absorbs a huge ammount of energy. This works especially well in dry climates. If you are in CA, its going to work like a champ.

For an AC unit to work, you would need to shut all the vents on the GH. Because the air being cooled needs to be the same air recirculating. You can't have a vent or fan pulling fresh hot air in and expect to cool it with an AC. Its going to run nonstop and never cool the GH to where you need it.

Im not trying to poo poo you either. Im a commericial nurseryman and have lots of experience in this area.
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You live in Borrego Springs? Thats the hottest place in county. With it being 110 average from may through sept.
 
7

757growin

Well-Known Member
NirvanaMesa said:
Bug infestations are a sign of soft plant tissue. Not all plants will develop chlorosis but some tend to in a GH because of the extra heat and humidity. Plants grow faster and tend to not harden off as well as if they would outside in the elements. Thats why they are bug and mildew magnets. Its not strange growh its just more soft and suseptible to attack.

As far as cooling, absolutely shade cloth and fans. Thats all I use most of the time. My fan pulls in 1.5X the volume of the GH every minute. Its a big ass fan and its on a 30$ thermostat and keeps the temps right where I want them. But when its 100F outside, pulling in hot air doesnt help. Right now its 70F outside in december and I can keep my GH around 90F inside with just a fan. During summer I have to run 50% shade and a mist system. Theres no way to passively cool your GH if the outside air is hotter than what you want the inside to be. Its always going to be hotter inside a GH than out if the sun is shining. Now if you live somewhere with mild weather then you may be able to get by without any knd of evap or other cooling other than a fan. And in that case a GH would also be extending your season and providing extra heat you need. Where if you live in southern CA like me, a GH isnt helping a lot during most of the year. We already have a very long growing season, warm dry weather etc. It becomes a pain during summer to keep the temps below 100F. Thats why I am saying its better to just grow outside sometimes. Especially if you live somewhere that can easily pull off an outdoor grow and no need a GH. Keeping your neighbors from seeing what you are growing is not a great reason to get a GH. Trying to extend your growing season or raise your temps for better growth are good reasons. Im not knocking anyone for wanting a GH to keep whats inside out of sight, Im just saying it may be more trouble than you are expecting.

I have done tomatoes in the GH in winter. They do fine. I propogate avocado trees, cherimoya trees, mango trees, dragonfruit cactus, pineapples and a few others for commercial nursery stock. Avocados do the worst in the GH. Very prone to aphid attack and chlorosis. I have to feed the trees systemic pesticide to keep the aphids under control. My GH is absolutely golden this time of year though. Im propogating stuff that would otherwise not grow outside this time of year. And I will have them ready for sale in spring. And I could probably grow great weed in there this time of year too except for the photoperiod is too short. Would need supplemental lighting to veg the plants and keep them happy on cloudy days.

If you do some digging or talk to the big pot growers in Northern CA, they will tell you they only use the GH to keep the rain off their plants or to do light dep. They will tell you the plants are healthier and less prone to issues when they can leave the cover off the GH. Now I have no idea where anyone else is located in this thread. No one mentioned what state they are in. If you guys are in a more cool climate or one with more rain, humidity etc you may have totally different experience and or set of problems. I just want people to realize when you throw down a GH, its not just automatically a perfect growing environment. Its most likely going to need some adjusting and there will probably be unforseen issues. And it will probably cost more than you were origjnally expecting to get it all sorted out.
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Check out the santa ysabel rez if you can. They run about 12 greenhouses there year round. I see their lights on every night and morning this time of year.
 
7

757growin

Well-Known Member
NirvanaMesa said:
Bug infestations are a sign of soft plant tissue. Not all plants will develop chlorosis but some tend to in a GH because of the extra heat and humidity. Plants grow faster and tend to not harden off as well as if they would outside in the elements. Thats why they are bug and mildew magnets. Its not strange growh its just more soft and suseptible to attack.

As far as cooling, absolutely shade cloth and fans. Thats all I use most of the time. My fan pulls in 1.5X the volume of the GH every minute. Its a big ass fan and its on a 30$ thermostat and keeps the temps right where I want them. But when its 100F outside, pulling in hot air doesnt help. Right now its 70F outside in december and I can keep my GH around 90F inside with just a fan. During summer I have to run 50% shade and a mist system. Theres no way to passively cool your GH if the outside air is hotter than what you want the inside to be. Its always going to be hotter inside a GH than out if the sun is shining. Now if you live somewhere with mild weather then you may be able to get by without any knd of evap or other cooling other than a fan. And in that case a GH would also be extending your season and providing extra heat you need. Where if you live in southern CA like me, a GH isnt helping a lot during most of the year. We already have a very long growing season, warm dry weather etc. It becomes a pain during summer to keep the temps below 100F. Thats why I am saying its better to just grow outside sometimes. Especially if you live somewhere that can easily pull off an outdoor grow and no need a GH. Keeping your neighbors from seeing what you are growing is not a great reason to get a GH. Trying to extend your growing season or raise your temps for better growth are good reasons. Im not knocking anyone for wanting a GH to keep whats inside out of sight, Im just saying it may be more trouble than you are expecting.

I have done tomatoes in the GH in winter. They do fine. I propogate avocado trees, cherimoya trees, mango trees, dragonfruit cactus, pineapples and a few others for commercial nursery stock. Avocados do the worst in the GH. Very prone to aphid attack and chlorosis. I have to feed the trees systemic pesticide to keep the aphids under control. My GH is absolutely golden this time of year though. Im propogating stuff that would otherwise not grow outside this time of year. And I will have them ready for sale in spring. And I could probably grow great weed in there this time of year too except for the photoperiod is too short. Would need supplemental lighting to veg the plants and keep them happy on cloudy days.

If you do some digging or talk to the big pot growers in Northern CA, they will tell you they only use the GH to keep the rain off their plants or to do light dep. They will tell you the plants are healthier and less prone to issues when they can leave the cover off the GH. Now I have no idea where anyone else is located in this thread. No one mentioned what state they are in. If you guys are in a more cool climate or one with more rain, humidity etc you may have totally different experience and or set of problems. I just want people to realize when you throw down a GH, its not just automatically a perfect growing environment. Its most likely going to need some adjusting and there will probably be unforseen issues. And it will probably cost more than you were origjnally expecting to get it all sorted out.
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Pineapples? Who buying those? How much for your cherimoya? Any pics? Any decidous fruit trees? Im tree shopping! Any good wind break trees also.
 
petert

petert

Well-Known Member
NirvanaMesa said:
This is the hoop house I made. Its 48ft x 16ft x 8ft. Its not for growing pot but would work ok I guess. To be honest most plants are much happier outside of a greenhouse. Even indoors under lamps is better. Greenhouses tend to have a lot of issues. I think you would be better off growing in the guest house.



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I’d have to disagree with this comment. I’ve been growing on a fairly large scale for 12 years outdoors and the past 4 years Greenhouse AND outdoors! Aside from getting russets two years ago, my plants are happier in the GH, I can start earlier, finish later and the quality is between indoor and outdoor!
Then there is doing light Dep inside a greenhouse. For me this is perfect! I got three excellent harvests this year. The quality isn’t quite what my indoor hydro was.. but pretty darn close!!
 
petert

petert

Well-Known Member
MustangStudFarm said:
The biggest problem that I will be facing is extreme heat, it's too hot during the summer to have plants in direct sunlight for the full day. That is why I am suggesting a mini-split A/C and making it over sized, maybe a 2-3 ton. My 24,000btu Mitsubishi Mr. Slim works fine on my 1,200sqft house during the summer and I would like to think that it would work on a 400sqft greenhouse too. I'm often wrong about these things and that is why I am here. I wanted to use sunlight instead of indoor growing because I am finally legal and I don't have to hide it anymore.
Click to expand...
NirvanaMesa said:
I doubt its too hot to have plants in full sun all day unless you live in AZ or the desert parts of CA. I live 16 miles inland in the hottest area of San Diego county and can grow plants in full sun on the side of a south facing hill. We even had a few days of 115F back in June. The plants dont seem to care at all. As long as they are watered they do just fine in crazy heat.

I think you will find that pretty much no one runs AC in a greenhouse. Greenhouses get way way hotter than a house as they absorb and trap all the energy from the sun. People typically use evaporative cooling walls or high pressure mist systems to cool a GH. When water goes from liquid to gas state it absorbs a huge ammount of energy. This works especially well in dry climates. If you are in CA, its going to work like a champ.

For an AC unit to work, you would need to shut all the vents on the GH. Because the air being cooled needs to be the same air recirculating. You can't have a vent or fan pulling fresh hot air in and expect to cool it with an AC. Its going to run nonstop and never cool the GH to where you need it.

Im not trying to poo poo you either. Im a commericial nurseryman and have lots of experience in this area.
Click to expand...
Mid summer heatwaves my greenhouse is between 100-110 and like other greenhouse growers in my area. They arch upwards towards the sun! I keep the plants hydrated and they thrive!
 
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