A green house isn't so easy as I thought to use...

[chuck_n_grace]

Hi,
I must admit I was a bit naive. Place plants on shelves in the tiny 8'x8' greenhouse and watch them grow throughout the winter.

We've been managing temperatures. Last night was below freezing (28°F) and this afternoon the outside temp was 61°F, with internal greenhouse temp of about 81°F. We're finally developing a system.

1. If outside temp drops below 45°F, turn on the greenhouse heater. A bit of a cost, but we do have nearly 400 plants growing. The temperature inside stays about 15°F warmer than the outside.
2. When temp rises above 50°F outside, we turn off the heater.
3. As the greenhouse temp hits 80°F, we open the greenhouse transom and the door.

Alas, we are learning how to do this....however it has been our latest "ball and chain" in our lives.

I'm pricing those mechanical window openers that are temperature sensitive. I might be able to add a couple of them to help us out as spring and summer approaches. Of course they are $75 each...need something cheaper.

I'm curious if any of you feel "chained" to your greenhouse when you've got plants depending on ideal temps?

Regards,
Chuck

[Durgan]

Hi,
I must admit I was a bit naive. Place plants on shelves in the tiny 8'x8' greenhouse and watch them grow throughout the winter.

We've been managing temperatures. Last night was below freezing (28°F) and this afternoon the outside temp was 61°F, with internal greenhouse temp of about 81°F. We're finally developing a system.

1. If outside temp drops below 45°F, turn on the greenhouse heater. A bit of a cost, but we do have nearly 400 plants growing. The temperature inside stays about 15°F warmer than the outside.
2. When temp rises above 50°F outside, we turn off the heater.
3. As the greenhouse temp hits 80°F, we open the greenhouse transom and the door.

Alas, we are learning how to do this....however it has been our latest "ball and chain" in our lives.

I'm pricing those mechanical window openers that are temperature sensitive. I might be able to add a couple of them to help us out as spring and summer approaches. Of course they are $75 each...need something cheaper.

I'm curious if any of you feel "chained" to your greenhouse when you've got plants depending on ideal temps?

Regards,
Chuck

I only use my greenhouse for producing plants for outdoor planting the last week of May. The outside temperature is from 0 to about minus 15C at night. I heat with natural gas, and can keep the temperature just above freezing in the center of the green house. In my case the greenhouse is mostly for the extra light. It will be heavily used starting about the first of March, since the temperatures below zero are relatively rare. To produce food meaning getting a temperature that is suitable in the dead of winter would be prohibitively expensive. During the day is the Sun shines I have to open the doors to keep the temperature down. Yes maintaining a constant temperature is a hassle. http://www.durgan.org/URL/?HKERY 5 November 2010 Greenhouse on Deck.

http://www.durgan.org/URL/?HNDAH 31 January 2010 Tah Tsai, Rosette Pak Choy
Stir fried one plant of Tah Tsai in butter and a bit of soy sauce today,
and tried some raw. It was a fine tasting green. It grows readily at
the relatively low temperatures in the greenhouse. Other names:Tah Tsai,
Tai Cai, Rosette Pak Choy, Wuta Cai, Tatsoi
Background Information.
http://durgan.org/2011/?p=33 23 January 2011 Repotting Pak Choy
http://durgan.org/2011/?p=29 2 January 2011 Pak Choy in Greenhouse
http://durgan.org/2011/?p=25 10 November 2010 Indoor Seed Planting

[chuck_n_grace]

Hi Durgan,
Just took a look at your greenhouse. It's very nice and well built. We to used the corrugated plastic...but only for the roof. Like you we used the screws with the rubber grommet...still managed to get a leak or two. However I think that is because the screw holes were stripped out.

From what I've read, some people would be inclined to put in some sort of heat sinking deck inside the greenhouse. I'm not sure if that would increase inside temps or not where you live. Maybe some black metal containers full of water on the north side. Plastic containers certainly have not helped much in our greenhouse.

I'm wondering if a second layer of corrugated plastic would help much in the winter on the inside? R ratings are very low though.

Have you looked at the automatic mechanical window openers? They're about 75 dollars. I've not used them before.

Enjoyed the Pak Choy pics....nice contrast with the snow.

Regards,
Chuck

[Carltonian Man]

Hi Chuck

We have a heavier duty auto vent opener on a double pane toughened glass window and another on a louvre side vent. Both work really well and can be left to get on with it once set. Didn't pay anything like 75 dollars though, more like these
http://www.amazon.co.uk/s/?ie=UTF8&keyw ... 8ghkmf3e_b

[chuck_n_grace]

Carltonian Man,
Thanks for the link. Those are exactly what I'm looking for. I'm certain the wants I saw on amazon.com (non-UK) were more expensive...I'm hoping I'm wrong.

Are you pleased with how well they function?

Thanks,
Chuck

[Carltonian Man]

Are you pleased with how well they function?

Really pleased, wouldn’t like to be without them. Our greenhouse is unheated and in a sheltered position but after about 10.00 it’s subject to full sun. Early in the day it can be rather nippy in there but once the sun hits, temperatures soar. I’ve got the top vent starting to open at about 70F and the side louvre starting at 80F to create a through draught. On days when the sun is in and out it’s quite interesting to watch how well the auto openers control things. They’re easy to adjust but I find now they don’t need touching from one year to the next.