Costco Greenhouses?

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Been looking at some greenhouses on Costco, some seem within a range that I'm comfortable with. Has anyone gotten one of these?

This is the one I'd want, but I don't see it for sale on their site now - was told it would be up in spring, but it's spring now. I swear I saw a link from here where it was still for sale, so I'm wondering if it sold out - can't seem to find the thread now.

04_22_SS_BuySmart_Greenhouse_03.jpg



These two seem plausible as well:



(the eternal go big or go home debate, under a grand would be fantastic though)

I'm aware I'd need to get a fan to vent it during the summer, but it would be primarily intended for keeping trees during the winter with a heater running. For the summer months I see you can stake shade cloth and use a fan to control heat, but I don't know if it's a firm requirement that it be viable for summer.

Curious if anyone has opinions on these. I wouldn't mind building from scratch, I just don't really know where to get all the stuff and feel like I'd probably end up spending just as much anyways, or close enough that when you factor in personal labor it'd be about even in my head.
 
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Oh, and the other concern I had would be - what about in winter when you get a blue sky day with the sun beating down, I'm curious how concerned I have to be about it heating up too much. Sounds like there's greenhouse whitewash that you can paint on the poly to control this, but I've not researched that yet.
 

jimib

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I have the Palram…a small one. I’ve used it to put hearty trees out there in the winter with no issues. Just keep the air circulating. I cover it with canvas dropcloth rather than the paint. This way I could take it off or put it back on as needed, the heat up rather quickly in direct sunlight.
I have a vent that stays open during the summer, although I don’t really keep anything in there during the summer.
You have to be careful heating it in the winter. Space heaters typically aren’t supposed to be ran off of an extension cord. It’s an easy way to get a fire started.
 
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I have the Palram…a small one. I’ve used it to put hearty trees out there in the winter with no issues. Just keep the air circulating. I cover it with canvas dropcloth rather than the paint. This way I could take it off or put it back on as needed, the heat up rather quickly in direct sunlight.
I have a vent that stays open during the summer, although I don’t really keep anything in there during the summer.
You have to be careful heating it in the winter. Space heaters typically aren’t supposed to be ran off of an extension cord. It’s an easy way to get a fire started.

I have a greenhouse heater :). SUPPOSEDLY I think it's OK but I could be totally mistaken about that, I don't think it's the same as a space heater in terms of how hot coils can get, it stays cool to the touch everywhere.
 

rockm

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Been looking at some greenhouses on Costco, some seem within a range that I'm comfortable with. Has anyone gotten one of these?

This is the one I'd want, but I don't see it for sale on their site now - was told it would be up in spring, but it's spring now. I swear I saw a link from here where it was still for sale, so I'm wondering if it sold out - can't seem to find the thread now.

04_22_SS_BuySmart_Greenhouse_03.jpg



These two seem plausible as well:



(the eternal go big or go home debate, under a grand would be fantastic though)

I'm aware I'd need to get a fan to vent it during the summer, but it would be primarily intended for keeping trees during the winter with a heater running. For the summer months I see you can stake shade cloth and use a fan to control heat, but I don't know if it's a firm requirement that it be viable for summer.

Curious if anyone has opinions on these. I wouldn't mind building from scratch, I just don't really know where to get all the stuff and feel like I'd probably end up spending just as much anyways, or close enough that when you factor in personal labor it'd be about even in my head.
My two cents--Unless you have the proper heat venting and/or heater for the winter, this is a problem that can kill your trees and possibly you if you're not careful.

A space heater is asking for electrocution, or a fire, or both--I Don't know of any space heaters (other than special purpose greenhouse heaters) that are rated for outdoor use.. Most will say right on their labels "not for outdoor use." A greenhouse this small is likely to heat up very quickly and cool down very quickly at night. I wouldn't store anything in it for the winter...likely too cold, too hot, or both simultaneously.

Bigger is better with a greenhouse. The more mass, the more time it takes to cool down/heat up. FWIW, this kind of thing is more trouble than it's worth. It's just too small. I'd get two, maybe three, of my trees inside of it comfortably.
 

jimib

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I have a greenhouse heater :). SUPPOSEDLY I think it's OK but I could be totally mistaken about that, I don't think it's the same as a space heater in terms of how hot coils can get, it stays cool to the touch everywhere.
It’s not so much about it getting hot as it is the amps that it pulls. I had mine hooked up on a Bayide thermostat. It worked pretty good, but when it got super cold it would actually trip the fuse in the thermostat. When I tied it in directly to the extension cord, I found at the end of the cord got incredibly hot. Then I started doing my research. I should’ve done that first. Yours may be different.
 

jimib

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Since I’m bored at work, I looked up the greenhouse heater you have. I found this in the “questions answered”.
 

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Since I’m bored at work, I looked up the greenhouse heater you have. I found this in the “questions answered”.

Thanks! I was using a pretty heavy duty cord, I'll have to verify. Right now I'm definitely thinking of running an underground extension cord of some kind but that may be a terrible idea. I was thinking of having it set away from the house. May need to do more research on this.

My two cents--Unless you have the proper heat venting and/or heater for the winter, this is a problem that can kill your trees and possibly you if you're not careful.

A space heater is asking for electrocution, or a fire, or both--I Don't know of any space heaters (other than special purpose greenhouse heaters) that are rated for outdoor use.. Most will say right on their labels "not for outdoor use." A greenhouse this small is likely to heat up very quickly and cool down very quickly at night. I wouldn't store anything in it for the winter...likely too cold, too hot, or both simultaneously.

Bigger is better with a greenhouse. The more mass, the more time it takes to cool down/heat up. FWIW, this kind of thing is more trouble than it's worth. It's just too small. I'd get two, maybe three, of my trees inside of it comfortably.

Yes for sure, the greenhouse heater I have, as far as I am aware, intended for this purpose, so I think it's OK. Definitely not a standard space heater.

I tend to stick on the smaller side with my trees, so I was thinking it might be viable. The 8x12 in particular seemed like it could work, but I have zero idea how small "too small" is for a greenhouse. You're right though, I know plenty of people with economically sized sheds that they never ever used because once you put a single shovel in it, it's already looking full.
 

rockm

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Thanks! I was using a pretty heavy duty cord, I'll have to verify. Right now I'm definitely thinking of running an underground extension cord of some kind but that may be a terrible idea. I was thinking of having it set away from the house. May need to do more research on this.



Yes for sure, the greenhouse heater I have, as far as I am aware, intended for this purpose, so I think it's OK. Definitely not a standard space heater.

I tend to stick on the smaller side with my trees, so I was thinking it might be viable. The 8x12 in particular seemed like it could work, but I have zero idea how small "too small" is for a greenhouse. You're right though, I know plenty of people with economically sized sheds that they never ever used because once you put a single shovel in it, it's already looking full.
Smaller trees would only compound the rapid heat/cool problem. Small pots heat up and cool down more quickly, as such they'd follow the temp shifts in a small space more quickly.

BTW, if you only have a hunch that the heater you have is a greenhouse heater, I'd make SURE it is...the heater will be exposed to a lot of moisture--wet and electricity are a bad mix. Also most of the space heaters I've seen specifically recommend NOT using extension cords. I'd think to be completely safe, you'd probably have to run a dedicated (protected) line from your electrical box. Hooking a heater up to a standard outlet and leaving it can overheat the supply line to the outlet...I know the line for my inside space heaters get warm to the touch when they're used...

Not trying to discourage you really, but this is more complicated safety and tree wise than it seems.
 

Eckhoffw

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I’ve heard people using 50 gallon drums full of water as heat sinks in the winter, so warming and cooling isn’t so drastic.
I will be putting up a 10x12 harbor freight greenhouse as soon as the ground thaws.
 
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Smaller trees would only compound the rapid heat/cool problem. Small pots heat up and cool down more quickly, as such they'd follow the temp shifts in a small space more quickly.

BTW, if you only have a hunch that the heater you have is a greenhouse heater, I'd make SURE it is...the heater will be exposed to a lot of moisture--wet and electricity are a bad mix. Also most of the space heaters I've seen specifically recommend NOT using extension cords. I'd think to be completely safe, you'd probably have to run a dedicated (protected) line from your electrical box. Hooking a heater up to a standard outlet and leaving it can overheat the supply line to the outlet...I know the line for my inside space heaters get warm to the touch when they're used...

Not trying to discourage you really, but this is more complicated safety and tree wise than it seems.

No I definitely appreciate it. What I have is a greenhouse heater for smaller spaces, what I don't know is how it stacks up against ones you can't buy via next day delivery on Amazon :p

I've seen too many products that claim to be one thing but are bad at the job they're supposed to do to say 100% that I trust it, it worked fantastic this past winter though.
 
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I guess the question is whether or not this is actually viable at all at this scale, I just don't have room for a house sized greenhouse haha
 

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I’ve heard people using 50 gallon drums full of water as heat sinks in the winter, so warming and cooling isn’t so drastic.
I will be putting up a 10x12 harbor freight greenhouse as soon as the ground thaws.
You can use those in big greenhouses, but the size he's looking at here they'd likely take up too much floor space.
The 5 g/L water jugs will do it, or even just plastic milk jugs full of water, so they can fit on or under the shelves. Just fill every spare nook with them and you boost the mass allot. You still run the risk of individual jugs freezing in the cold spots, but you'll balance the temperature pretty well. If freezing is the concern, you can paint the jugs dark colors so they heat up more during the day.
Sandbags- frankly anything that adds mass- are also practical for building the thermal battery, but not as convenient as water jugs.
I guess the question is whether or not this is actually viable at all at this scale, I just don't have room for a house sized greenhouse haha
If you can get the right placement relative to the house and sun exposure, boost the thermal mass like discussed, and a small heater, you might be ok. Automatic vent openers will help allot with the heat, too, though you might find yourself wanting to add a vent or two at the bottom also.
You might not keep it warm or stable enough for growing mid-winter, but you could keep it above 40F and overwinter your hardier tropicals.
 
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You can use those in big greenhouses, but the size he's looking at here they'd likely take up too much floor space.
The 5 g/L water jugs will do it, or even just plastic milk jugs full of water, so they can fit on or under the shelves. Just fill every spare nook with them and you boost the mass allot. You still run the risk of individual jugs freezing in the cold spots, but you'll balance the temperature pretty well. If freezing is the concern, you can paint the jugs dark colors so they heat up more during the day.
Sandbags- frankly anything that adds mass- are also practical for building the thermal battery, but not as convenient as water jugs.

If you can get the right placement relative to the house and sun exposure, boost the thermal mass like discussed, and a small heater, you might be ok. Automatic vent openers will help allot with the heat, too, though you might find yourself wanting to add a vent or two at the bottom also.
You might not keep it warm or stable enough for growing mid-winter, but you could keep it above 40F and overwinter your hardier tropicals.

My goal is to have a place to keep at around 35 - it's not meant for tropicals but rather for more hardy plants. My thinking is that even if they warm up earlier in spring, the greenhouse will be such that they won't be damaged by flash drops in temp, and that I may be able to keep things like pomegranate and olive in there to give them a dormancy period.

It's definitely possible that this isn't my best idea, the spot I was thinking of gets a lot of morning sun in particular but later in the day should have some shade. I just need something better and more controllable / less janky than what I did last winter, I think.
 

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My goal is to have a place to keep at around 35 - it's not meant for tropicals but rather for more hardy plants. My thinking is that even if they warm up earlier in spring, the greenhouse will be such that they won't be damaged by flash drops in temp, and that I may be able to keep things like pomegranate and olive in there to give them a dormancy period.

It's definitely possible that this isn't my best idea, the spot I was thinking of gets a lot of morning sun in particular but later in the day should have some shade. I just need something better and more controllable / less janky than what I did last winter, I think.
You and I both. We'll see where the priorities land when the tax return comes in.

If you're really only thinking of keeping it above freezing, then finding a spot against the house and building up some sort of thermal battery inside should about do it except for the worst of winter. For that you might see if there's some sort of radiant type heater so you don't accidently scorch any nearby trees.
Out here it's not hard to find livestock trough heaters- they just float in a water trough to keep it from freezing over- and those are designed for extension cords. I've heard of people using them in water tanks in green houses to add an extra 5F to their water thermal batteries. Theoretically you could use one or two to make a circulated water radiated heating system with a water tank, some hoses and a backflow valve. I've only heard people talk about this one, but haven't seen it in person. It'd certainly do the trick around here, but I'm not certain about MA.
 

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I purchased a Palram 8 by 12 in 2013. Was slow and tricky to put together by myself but it has worked very well over the past nine years!
I use a Cafaro Greenhous space heater that simply turns on for frost control, and a fan for circulation to prevent humidity issues in the winter. Primarily for winter protection of certain species, newly grafted trees or young seedlings and cuttings. The green house sits empty from mid April till mid October unless special projects underway! Heater has functioned well and has only been used on the frost setting for the same length of time.
Was an inexpensive option compared to most and has met my needs.
I did pour a cement pad to provide better structural integrity. Bottom rails are bolted to the cement pad. If I had it to do over again I would add a drain in the cement floor to ease the interior mess from constant watering. I would also purchase shade cover for more extended use of the greenhouse early spring. This would allow for longer period of time for cuttings and seedlings before having to set them out.
 

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I purchased a Palram 8 by 12 in 2013. Was slow and tricky to put together by myself but it has worked very well over the past nine years!
I use a Cafaro Greenhous space heater that simply turns on for frost control, and a fan for circulation to prevent humidity issues in the winter. Primarily for winter protection of certain species, newly grafted trees or young seedlings and cuttings. The green house sits empty from mid April till mid October unless special projects underway! Heater has functioned well and has only been used on the frost setting for the same length of time.
Was an inexpensive option compared to most and has met my needs.
I did pour a cement pad to provide better structural integrity. Bottom rails are bolted to the cement pad. If I had it to do over again I would add a drain in the cement floor to ease the interior mess from constant watering. I would also purchase shade cover for more extended use of the greenhouse early spring. This would allow for longer period of time for cuttings and seedlings before having to set them out.

Very nice. Glad I asked, a cement pad is exactly the kind of thing I’d never think of myself and is so obviously necessary now that you mention it. Same goes for a drain!
 

Eckhoffw

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I purchased a Palram 8 by 12 in 2013. Was slow and tricky to put together by myself but it has worked very well over the past nine years!
I use a Cafaro Greenhous space heater that simply turns on for frost control, and a fan for circulation to prevent humidity issues in the winter. Primarily for winter protection of certain species, newly grafted trees or young seedlings and cuttings. The green house sits empty from mid April till mid October unless special projects underway! Heater has functioned well and has only been used on the frost setting for the same length of time.
Was an inexpensive option compared to most and has met my needs.
I did pour a cement pad to provide better structural integrity. Bottom rails are bolted to the cement pad. If I had it to do over again I would add a drain in the cement floor to ease the interior mess from constant watering. I would also purchase shade cover for more extended use of the greenhouse early spring. This would allow for longer period of time for cuttings and seedlings before having to set them out.
Thanks for your info. I will be looking for a similar heating setup once I get there. May I ask what you use?
 

River's Edge

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Thanks for your info. I will be looking for a similar heating setup once I get there. May I ask what you use?
I found many options but chose a " Cafaro" brand. Was approximately $125 at the time. 650 watt.

The twin-wall polycarbonate panels are a good choice, less likely to break and can be repositioned if they bend. I had a large branch from an overhanging tree fall on the roof. It punched out the panel but I was able to straighten and reposition the panel for reuse. Other materials would have been shattered and need replacement I am sure.
 
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