Hi Mike -

This is a great thread...one that I am very interested in as I am considering upgrading my greenhouse in the spring.

A few questions:

1) What kind of greenhouse do you own (brand)?
2) How does it hold up to snow load?
3) What kind of heater do you run in it?
4) When it is as sealed up as it is with the bubble wrap, how do you get fresh air in?
5) Do you run a fan in it for air circulation?

Thanks!

Tom

Does the green let enough light in?

Hi there Tom...Realise your ??'s were addressed to Mike but I thought I'd tell you of my experiences....

Here in the UK we can buy kits consisting of a roll of bubble wrap and some plastic clips that fasten into the channels that run along the aluminium greenhouse frames. The clips keep the bubble wrap an inch or so away from the glass giving it a good insulating inner layer. They cost around 15pounds (my pound sign appears as a square for some reason!!) for an 8x6 g/h kit. I have used them for over 30years now. Our current g/h is a home made wooden lean too type so we just drawing pin the b/wrap to the inside of the frames.
I also have aluminium shelving and staging which can be very cold so I put sheets of polystyrene on the staging and stand pots in saucers on this to give them some more warmth.

I have only ever used the clear b/wrap which does cut down some of the natural light, but as most of the plants are not actively growing, it doesn't matter. I dont know if
the green type would have an adverse effect or not.

The wrap can be cut and fastened to the windows allowing them to be opened as normal and I use a fan heater to keep the temps above freezing and also to help with air circulation. The electricity cost is relatively small as the heater is on a thermostat.
Gill from the UK.

I'll be a-reading here! Our plastic greenhouse here is 16 by 20 feet...heck of a lot larger than most everybody else's. Very curious about both the cost savings and any differences in lighting with it on, and how the plastic wrap would affect the rate at which the greenhouse heats up with the sun out, if at all...in winter we do have a few sunny days. Any and all specifics, please! So appreciated. If anyone has recommendations as far as the specific product/pool solar cover brand to get, that'd be great too.

Colleen

Well everyone!

Look what I found poking around here at the forums tonight.

If this older thread that I linked at the bottom of my post doesn't help, then I don't know what will.
I will also take some pics of mine wrapped up. Like I already told you all, it's the best thing I could of ever done to mine.

Yes, even on cloudy days, my greenhouse is staying warmer than it would left unprotected. I know for sure my heaters are working a lot less to continually heat up mine.

Hope this helps many here. And look, it is an older thread from the "Greenhouse" forums that is working for many here!
Right now it is 28 degrees out and I have a reading of 62 degrees with one space heater on at the moment while the other waits for the temps to drop under 60 before it kicks on.

Tom, I have this one. It is a Snap and Grow 6x8
Here is the link

http://www.outdora.com/18725hg6008-6-x-8-snap-and-grow-silver-greenhouse.html

It is intended for year round use. According to the company, very solid for my our area even in snow storms. If my little canvas one held up last year, this durable one will be first class.
I bought a small ceramic space heater at Lowe's for 39.99. and I have a back up of a coil small space heater. They can both be set at certain temps or thermostat controllable.
I have an auto opener that I set to open once the temps reach 70 degrees in there. All I had to do was slice the cover to allow the vent to open as the extra lip of the cover falls into the greenhouse.
Yes, I run a small fan in one corner of the greenhouse on rotate and air is evenly distributed throughout.

Tom, I hope this helps you:-)

Time for bed and good night to all.

Mike

Here is a link that might be useful: How 'Solar Covers' are a blessing for many!

Move to Florida!!
If it's less than 60 degrees outside, I don't leave the house!
Matthew

I hope anyone who has struggled to keep their greenhouse warm during the winter months has read this:-)

Mike

Good morning, Mike!
I'm looking forward to pics of your bubble-wrapped greenhouse!
This morning, it is 22F here....brrrr.....

Josh

First day of winter - 53F and sunny in Sudbury, MA...yahoo!

T

Matthew you have the best suggestion.

Mike maybe it will work better on the GH then it did on the pool. I'm willing to give almost anything a try. I wonder if I should disconnet the automatic vent openers or make a few cuts in the cover so they are still able to open? I only run 1 19k BTU heater and it's plenty for a 10 x 12. The big GH is still an issue but at least that one runs on propane instead of electricity.

Oh Karyn:

The 16x24 would be perfect for your bigger house.
I had to cut of many feet to make mine fit my small greenhouse just right.

All I did was slit where the vent opens and when it closes, the cover rest flush with it again.

Wiat till you see the difference. I will snap a pic for you tomorrow when I get more time. I actually took a few this am that I will post for you all.

Mike;-)

You guys have any recommendations as far as where best to order the covers (Magni-Clear ones)? I'm looking at PC Pools currently.

Heating a 16-by-20 greenhouse. Sigh, yes, a struggle. This would be a huge investment, so any advice is super appreciated.

Here is a link that might be useful: PC Pools

I hope this helps!

I googled that type, which by the way looks great and I came up with this.
I think just clear like the one I have still does just as good as a job. At least, that is what the pool experts say.
It lets all the light in possible, very bright while at the same time warms the house up nicely.

Mike

Here is a link that might be useful: Pool covers

Mike did you tack the edges down along the vent cover or anything to keep them from being blown by the wind?

A 16 x 24 solar cover would cover less then 1/8 of the bigger GH. The propane tanks have already been filled anyway and that should last until the end of Feb.

I'm only considering the solar cover for the small GH. I wish I hadn't trashed the old solar cover but I never thought I'd have another use for it. Besides that the thing you roll it up on took up so much space.

Thanks for the idea. I can spend the money I save on utilities on more plants. lol

Karyn, I thought I would take a couple of pics for everyone.

The vent area only has a small slit to allow it to open and the whole house has the whole cover tied around the house like gift wrapping paper.

Here you go.
{{!gwi}}

{{!gwi}}

{{!gwi}}

Lots of sunlight is still let in warming the interior in even distribution and much more rapidly as soon as the sun reflects it.

{{!gwi}}

{{!gwi}}

The temps are at 20 degrees this am. I had a reading of 55 degrees with the only one space heater running set on 60. Even the back up one was not on. Now that is going to save me big bucks! Yahoo.

Mike

Very nice, Mike!
Thanks for taking these pics.
I bet it's awesome stepping into that greenhouse!

Josh

Thanks for the pics and information, Mike. Very helpful!

Speaking of 'stepping into that greenhouse', how do you get inside it now?

T

Hey Tom.

I left the front piece of the cover long enough to just undue the bungie cord and lift it up. After opening the door, that piece of cover will drape to the floor not allowing the cold air into the house while I tend to it.

After I am out, I close the door, then fold the cover back up and then strap the bungie cord back over it again. Very simple.

Have a very merry one buddy!

Took a trip to the Bonsai shop today and my dear friend there gave me a couple of nice plants once again. I will share with you after taking pics

Mike

Hello, I dont know if this is of any help or not , i dont know what kind of GH every one has, but mine was a 24x40 ft Jaderloon,it was covered with plastic, I had 2 layers of plastic on the house and something that looked similar to a hair dryer it was called an inflation blower and it was attached to a rib and it blew air in between the two layers of plastic and made a huge air pocket between them and it was a great insulater, and I also had a couple of haf fans running. And it held up really well despite my cat climbing all over it and digging in his claws >^..^

Mike -

Gotta love the G-man - definitely post the pics.

He gave me a sweet Aloe marlothii and a couple of baby cycads that he no longer had room for last year. Can't wait for my yearly spring ritual of pruning some of my bonsai with him...only three months from now!

T

Those are some good ideas for keeping the greenhouse warm!

We use double layer poly, with fiberglass sides, and this time of year the gas bill is through the roof. We had a week when temps were dropping into the 30's at night and it def hurts the ol pocket book.

I have put all of my colder sensitive plants in 1 smaller gh that i keep the heat set at 50, while in the large house the thermostat gets turned down to 45. A lot of the plants actually seem to be enjoying the lower temps.

Was just thinking I would also share this info if people were looking for some more efficient ways to heat their greenhouses. We have greenhouses heated both by forced air (hanging gas powered heaters) as well as bench top heating powered by a boiler system.

The boiler system is by far the way to go. They are even making some smaller systems these days that the hobbiest can benefit from. If you are not familiar with how the benchtop heating systems works, a "boiler" looks more like an AC unit sits outside the greenhouse (these can be up to 99% efficient) and heats water that is passed through small tubes under the benches to directly heat the roots of the pots (the water is passed through the tubes via a pump). The heat also warms the air via conduction and warms the rest of the greenhouse. Since the boilers are so efficient there is a lot less heat wasted out the exhaust of the heater. We have been using a couple systems like this to heat several acres of greenhouses for the past 10 years and the cost savings is amazing.

Thanks for that Ggarner and

Tom, yes, less than 3 months now! I can't wait to see what is there next time.

Mike

hi MY GREENHOUSE IS 8X6 WHAT I USE IS WHITE FLEECE OVER TOP OF PLANTS ONE 40 WATT BULB IN A TIN ONE SMALL FAN BLOWING OVER TOP OF TIN SENDING HEAT AROUND ONE SIDE AND ONE SMALL FAN BLOWING UP THE OTHER SIDE I ALSO FEED PLANTS WITH WORM TEA I HAVE ONLY PLANTS FROM LAST YEAR LIKE PELARGONIUM AND FUCHSIAS AND SOME OTHER PLANTS TO TAKE CUTTINGS .THIS IS MY FIRST POST THANKS COINS

I know this is an old thread but I had a thought about pennyhal's question about green plastic letting enough light through. I believe that, as long as the green plastic is translucent, it should work but not as well as clear plastic.
We all know that the visible light spectrum (ROYGBIV) consists of multiple frequencies that determine the color. The color that reaches the eye, is the color that an object does not absorb or transmit. For example, the green material appears green because it absorbs the ROYBIV light and reflects the green light. Therefore, ROYBIV light is all able to either be transmitted through the plastic or absorbed and turned into energy. If the green plastic is transparent enough, the light will be transmitted. However, if the green plastic is too opaque, it will be absorbed.

Hope this helps.
Here's a link that can explain it better than I can.
http://www.physicsclassroom.com/class/light/Lesson-2/Light-Absorption,-Reflection,-and-Transmission