Hello everyone,
I have been eavesdropping on this great forum for a few days now, and decided to jump in with a question.
I have been using a 20x96 unheated high tunnel for a couple of years now in zone 7b where it gets awfully hot in the summertime. Roll-up sides would really be nice to have, and I would like your suggestions for the best method to use for this conversion. Currently I am using two layers of poly with air inflation.
Thanks,
Lynn
I have a greenhouse that length with two layers of plastic and the fan. I cannot even begin to imagine how you would do that because of the length and weight of the plastic.
Is there no way at all that you can put a large fan and shutters and electricity out there? Well, you already have the electricity because of the air inflation? You are using a small squirrel motor to inflate the plastic? I would put shutters and a fan in there in a heart beat. You have to have 220 electricity for the fan, which you probably don't have, but thats all.
That or take the plastic off in the summer. Or, if you don't keep plants in there in the summer, take the plastic off the gable ends. I take it the house is firmly, and I mean firmly attached to the ground? Cause if the wind blows hard and you have the gable ends open, that house is setting sail.
In my neck of Zone 7b, I dont need double poly.
If greenhouses made to have curtains can use double poly on top then surely you could do it with a hoop house.
The side curtain would be single poly.
I can only show a picture of a single poly tunnel house with side curtain.
good luck
Cricket
I guess it depends on what you are growing in it. We are all three of us in zone 7b-lol. I know in January, when I start the crop, I have to have a heater.
Cricket, this may be a stupid question, but aren't you in Alabama (Al-)? Isn't that a lot warmer than where I am?
Also, I noticed that you had shade cloth on one of your hoophouses-how come? I got the impression that all your plants were full sun.
So when you drop that plastic, is it weighted at the bottom, or do you just put something on top of it on the ground? How long does it take to put it up like that by yourself? I had a similiar arrangement on a cold frame, but it was only 40' long, and seemed much more manageable, than 100'. I love my fan!!
i love my fan too. I bought the large industrial fan at home depot for $300.
ok let me get my brain in order.
Yes i think it is slightly warmer here where i am at. I am right on the border of 7a and 7b. North Alabama.
Yes sometimes i just weigh down the curtain with compost manure bags but its not fun moving them things all the time.
I wish I had shorter Greenhouses so I could do my curtains differantly. I may cut them in half the next time I change the poly in 3-4 yrs.
Ok here goes and hope it makes since.
The best way to operate a homemade curtain is to attach the bottom of the poly to pvc with duct tape and roll it up some to make sure the tape stays attached at all times. At the end of the pvc you put a T on it. You can use a 5 foot piece of REbar to hold the pvc curtain in place.
YOu just put the rebar through the T and put the ground end of the rebar into a Pipe that you insert in the ground. like the gavinized pipe used for the greenhouse perlin. When you are ready to raise the curtain---you just remove the rebar and roll it up---and its best to roll it under and not over . Rain sets up in the poly if you roll it over. Hope this makes since.
Mean while ----until i get the time and money to do this home made curtain ---I have just screwed 1x2s to the bottom of the greenhouse base to hold my curtain down until it starts getting too hot. then i will take the screws out, put my 1x2s up in the barn, and let my curtains up. I let my curtains up permanantly about April 15. I use rope to hold my curtain up.
When it rains, and the curtains are up, the rain coming off the top of the greenhouse pours into the greenhouse washing the soil off my seedlings/ plants. Sooooo---I just pull my pallets away from the wall of the greenhouse to keep my plants from washing away. Straight sided greenhouses are much nicer but more expensive.
Now how do you put the curtain on the side to begin with. We use 2x4s and the U brackets that you use for putting the perlin on with.
It deffinately takes two people to do this. And you have to have short pieces of 2x4 to join each 2x4 together.
If i didnt make sense---just ask me. I may have left out a few details.
Cricket
I made a thread with web site that shows what i am trying to explain.
Hoophouse Construction instructions( thread)
That was a good website-very explainatory (sp-lol too tired to think) Wish I had it when I had that 40'cold frame. I jusst took the plastic off every day and at night secured it at the base with cuphooks that I pulled the plastic (doubled over with ductape and a hole in it) over. My own design lol can you tell??
Cricket-you still didn't tell me why you had shade cloth on the cold frame? Don;t your plants start to get leggy with it on?
I put that shade cloth on because when i got my plugs from dixie green they started to scorcth---even in the greenhouse so they must of grown them under a painted poly or white poly. I am only using a 30% shade cloth. Nothing is leggy. Its very bright in there.
I normally dont use the shade cloth until its near the end of spring and its much hotter and the sun is brighter to help cool the greenhouse.
I do have some impatiens in the greenhouse.
I harden the plants off by raising the side curtain. the plants get morning sun on one side and evening sun on the other side. If that makes sense.
AFter I am through transplanting in that greenhouse, I will most likely remove the shade cloth. without the shade --im burning up. Can almost water the transplants with my sweat.
Cricket
see-----not leggy
they look very nice Cricket- I grow my impatiens in the full sun in the greenhouse-it makes them stay lower and bloom faster, and I don;t have to use a growth retardent. I also keep them on the dry side. I don;t like to put impatiens in teh full sun outside. Its been my experience that while they do well in full sun in the ground-they don;t do well in the pots sitting outside in the sun. Go figure. I just take them out of the greenhouse and straight to the landscaper.
I forgot that you don;t have a fan system-it must get hot in there and now I can see the need for the shade cloth.
I use a shade cloth on one greenhouse in July when I am germinating pansies seeds-even with the fan going non-stop, its too hot in there w/out the shade cloth. Once I germ them, then I start to peel off the layers of shade cloth until they are off all the way.
Thanks for the quick feedback.
Eventually I would like to have permanent fans with tstat controlled dampers, but i've got to sell enough veggies to pay for it first. Right now I am using one 36" portable fan, and a couple of smaller box fans that I hang in the window openings on one end of the hoophouse. This helps, but it is still too hot. I purchased a white 40% shade cloth to try this year, but I have not put it on yet. I decided to try the white thinking it might be a little cooler than the black. When this poly wears out, I will probably replace it with a single layer.
The link showing the method for roll-up sides was very helpful. I think that might work, if the 100 ft. length is manageable.
That was a good pointer about the water drainage problem with curved sides. I hadn't considered what that might do to my outside beds.
I plant directly in the soil in the hoophouse. There are two 30" wide beds on the outsides, and three 40" wide beds in the interior. So far I have tried salad greens, carrots, radishes, spinach, beets, tomatoes, squash, and cucumber. Everything turned out pretty well except for the squash and cucumbers. The biggest problem I think was lack of pollination. I was hoping the roll-up sides would help with that too.
I use T-tape drip irrigation with pretty good success, but it's a pain to have to take it all up to rework the beds. What do you think about the overhead drip/mist systems?
I BEEN thinking about putting up a solid piece of poly in the middle of my curtain line and making two seperate roll up curtains. I need poly in the middle for when i let the curtains down. does that make sense?
I will never use over head drip systems. I dont want my plants to get water on them. That will cause alot of fungus and deseases in a greenhouse if you are not carefull. And I like to make sure my tomatoes dont get wet---could cause them to crack. I water from the soil line only. I very seldomly wet my plants.( produce plants)
Last year i took the poly off the greenhouse cause it was way too hot in there. The curtain was only 2 1/2 feet off the ground and not enough air circulation. As soon as I took the poly off---we got a hell storm. It beat my fruit up. I had holes in everything. Then we had rain storms and rain and more rain. Thats why i think the plants got some kind of desease. Too wetttttt. I should of put a fan between the rolls but I didnt have a fan back then.
Now i only have one fan but working on getting 2 more.
Last years tomato crop in greenhouse
this is when they started showing problems
