Hoophouse is in!
 

Hi all,

I haven't posted in a while--I spend most of my energy struggling to survive engineering classes.

Anyhow, I asked a farmer acquaintance for help setting up a hoophouse and last week we got it covered with plastic. It still needs some finishing work, but I've started putting in some seedlings.

http://farm3.static.flickr.com/2659/...bbf3b12bd8.jpg

Twenty by twenty-four foot hoophouse in our back yard. Winter makes everything look so bleak!


http://farm3.static.flickr.com/2501/...48be92ca74.jpg

Transplanted volunteer red russian kale seedling. I hope that it will happily overwinter under cover.


http://farm3.static.flickr.com/2617/...5bbe7d8077.jpg

Sunlight peeking through the double equipment doors behind some bald cypress saplings.

I wasn't sure that this project would go in this year, so we didn't have enough seedlings ready to go in for the winter. So this winter we'll only have some kale, cabbage, lettuce, and parsley going. I plan to try winter sowing vegetables under double covers as well in hopes of extra-early spring greens.

-Kris

Re: Hoophouse is in!
 

Looks real good there, Kris......thanks for the post and the photos.

Did you use double plastic on top, and are you using a blower to keep air in between ?

The metal hoops....they commercial jobs, or did you bend some EMT conduit ? I notice it looks like they don't go all the way down, but seem to stop on the side walls.

We're giving serious consideration to one next winter.....got too much in the way of house remodel this year to do it, but that's 'on the list'.

Re: Hoophouse is in!
 

Wow, Ralleia, I'm jealous! I'm hoping to put in a small greenhouse next spring, but it won't be anywhere near as large as yours. Nice going!

Re: Hoophouse is in!
 

Which discipline? Undergraduate?

Re: Hoophouse is in!
 

The hoops are commercial--I'll have to ask my farmer friend again what the manufacturer is. He usually does 200-foot houses, so mine is cobbled together from his spare parts.

The hoops go all the way to the ground--the side rails are in the way in my photos. Here's a couple photos from the 200-footers that the farmer has:

http://farm3.static.flickr.com/2718/...45246a1d56.jpg

http://farm3.static.flickr.com/2552/...5648f95134.jpg

They are indeed double plastic, and I have a blower, but that's not wired in yet.

Since I am a total newbie with hoophouses, I let the farmer direct what materials to use, but there's a couple modifications that I would like to consider for the future, especially when it comes time to replace the plastic:

I've heard of a technique where people put 3-5 layers of bubble wrap between the two layers of plastic to provide the air insulation without using a blower.

Also, a different grower that I know uses a double layer of a much more durable greenhouse cover, called Griffolyn TX-1200. I've been to his greenhouse a couple times and I think I'm in love with the stuff. http://www.reefindustries.com/upload...ecs/tx1200.pdf

During the day it's certainly more temperate within the hoophouse than without. By Wednesday we're supposed to be getting colder (lows in the single digits, highs in the teens), so that'll be a good test. I'm putting a remote temperature sensor in the house to monitor the highs and lows (so long as the batteries continue to work).

Re: Hoophouse is in!
 

Architectural engineering, third year of a five-year combined BS/MS in AE program. I plan to be specializing in lighting but taking all the mechanical (HVAC) classes as well.

Re: Hoophouse is in!
 

Very cool. Mechanical myself. I found HVAC to be rather dull, but I am a materials guy anyways. Best of luck to you. oh, and congrats on the greenhouse, it looks awesome.

Re: Hoophouse is in!
 

One thing the blower does besides provide an air insulation layer is also keep the top layer tight so it doesn't flap as bad in the wind and tear.....so bear that in mind if wind is an issue in your location.



Our little lean to greenhouse built into the bank is surprisingly temperate compared to outside. I put a high/low recording thermometer in it last year, and with NO heat, the lowest it went was just under 40 degrees with outside in the single digits. That would allow almost any cool crop to be grown. This year, we're experimenting with tomatoes and do have heat at nights ( propane ) trying to keep it in the 55+ range at night.

Re: Hoophouse is in!
 

is that a special plastic?

i built a leanto hot house last year and covered it in heavy duty plastic from home depot and it did not last a year due to sunlight deteriation.

i have since recovered it with clear corrigated plastic which was designed for outdoor usage

Re: Hoophouse is in!
 

wow this is what I.m looking at in the future.
For now I have this

Re: Hoophouse is in!
 

It's a special agricultural film called Tufflite. It's the 6-mil version and the manufacturer claims it will last four years, so it must be UV-stabilized.

That Griffolyn stuff that I really wanted is supposed to last at least five years in the Texas sun, so I'm sure it would last quite a bit longer up here. I have a sample of the stuff--there's a mesh encased in the layers and it doesn't even feel like plastic--it feels like a cross between plastic and fabric.

It got down to 21 degrees for several hours last night--the lowest temp recorded in the hoophouse was 23 degrees. I have some bad gaps around the doors that need to be weatherstripped. With the sun up it's currently six degrees above ambient in there and rising.

I had read that as well, and that some people using the bubble wrap plug in the blower when high winds are expected. It would be neat to get one of those home weather stations (with the windspeed meter and all) and wire the blower to come on above certain windspeeds.

That dream is a ways off. We've got a mess of remodeling projects as well--the most daunting of which is knocking out the old chimney and replacing it with a flue that goes straight up from the wood stove. The sweep told us last year that the flue liner stops short of where the stove goes into the chimney (dang house!) and we'd either need to put in a totally new flue pipe or break out the old one and replace it.

Do you have buried heating cables as well? A lot of plants will do better if at least their feet are kept warm.

What variety of tomatoes are you trying? Ones known for setting in cold conditions (I remember a variety called Siberia--I think I have another cold setting variety in my tomato seed collection as well).

It should be an interesting experiment. I'm trying to grow a small indeterminate type (pink ping pong) in a tall south-facing window. In the past I've grown miniature determinates (Red Robin and Orange Pixie) for winter tomatoes indoors, but didn't get enough of them to really justify the hassle. The best success I've ever had with winter tomatoes was a few years ago by bringing inside a glut of green tomatoes before the frost and setting them stem side down on a flat surface, not touching. They would slowly ripen. We also stored some of them in the 40-degree basement carefully packed in newspaper. We finished the last of them in January.

Re: Hoophouse is in!
 

We're using a variety specifically for greenhouses, Trust.....but I'm really curious about that Siberia variety (thanks ! ) after you posted it. I think we could maintain that 38 degree temp with almost no external heat source.....especially after I get some solar hot water plumbed in.

I do have one heating cable in one of the barrel halves, trying it as an experiment. At first, the two plants in that barrel took off way ahead of the others, but after some weeks, the others caught up, and now you basically can't tell any difference. We're having problems with fruit set.....clusters of flowers form, but most of them don't open enough to pollinate. We got some fruit set on a couple plants early on ( like mid Oct ), and tomatoes now about the size of baseballs on those plants, but then it seemed like flower opening stopped.

One thing I've read is too high a humidity is a problem. We open the door and let a roof vent fan run when it's warm enough, but I'm sorta scared to do that when it's under freezing temps. Have also tried cutting back on watering, adding gypsum ( calcium source ) to them, and spraying with a tomato spray that is supposed to encourage fruit set.....I'm thinking humidity is our problem....don't have a gauge in their, but it feels pretty high.