Greenhouses

Discussion in 'Gardening & Plant Propagation' started by MRoxy, Jun 19, 2005.

  1. MRoxy

    MRoxy New Member

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    Just incase you are wondering Yes Iam a newbie when it comes to starting new plants. I am looking at having a Greenhouse built this yr for next yrs growing season. Can anyone please explain to me how exactly a green house works. I would also love any advice from experinced users. Which is better glass or plastic if plastic how does the light get through it to feed the plants? does it have to have a watering source or can I do hand watering. please I can use any adive I can get.

    please and thank you
    Roxy
     
  2. MaineFarmMom

    MaineFarmMom Columnist, Feature Writer

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    A greenhouse holds in heat and protects plants in the cool months. You might need additional heat, depending on where you live. I heat mine with propane. On warm days anything solid in the greenhouse (barrels of water and the floor, for example) will warm up. These slow down cooling at the end of the day.

    I've never had glass so I can't be helpful with that.

    My greenhouse has six mil plastic (six millimeters thick). It's not as bright and it's not sunny like outside but there's plenty of light.

    You can hand water. I bring in the hose.

    You'll want a fan for air circulation; vents, window or an open door to keep it from getting too hot and too moist inside; benches of some sort to keep the seedlings on.

    http://thymeforewe.com/greenhouse.html This might be helpful.

    My greenhouse isn't fancy but it serves me well. Total cost for 12 x 24 was $600. I've upgraded the heater from what's shown in the pictures.
     

  3. Hank - Narita

    Hank - Narita Well-Known Member

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    Robin your greenhouse looks great. Ours is 12 x 12 ft. It is made from prefab panels bought at greenhouse supply. DH built it last year. We are in AZ and don't have extra heat. He did put in 2 doors. Our neighbor put in vents that open and one door in hers. It is twice our size. Definitely worth the time and money.
     
  4. skruzich

    skruzich Well-Known Member

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    You can also use foggers to cool the greenhouse instead of the fans. Fans run anywhere from 300 bucks on up to aroun 7000 dollars.
     
  5. MaineFarmMom

    MaineFarmMom Columnist, Feature Writer

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    My fan was under $100 and works well for the size of my greenhouse. I start planting seedlings out in May and finish in early June. If I'm careful to have the door open when I do chores in the morning and turn on the fan it's seldom over 90° in the greenhouse. I don't close it up at night when the weather is warm enough.
     
  6. skruzich

    skruzich Well-Known Member

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    I think the difference is where you are and where I am. I am in sunny ole georgia and that 100 dollar fan wouldn't even dent the heat here. We have to use a combination of fan plus coolers for the larger houses, and foggers for the smaller ones to keep the heat down to 75-85.
    I wish i could find a 48" fan for 100 dollars! That won't even cover the motors.
     
  7. MaineFarmMom

    MaineFarmMom Columnist, Feature Writer

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    I remember the heat. I used to live in Savannah. The timing of planting plays into it also. If it's gotten too hot in the greenhouse more than a few days the plants I have in there should have already been in the ground. By mid June my greenhouse should be empty. This year is an exception.

    I just came in from the greenhouse for one last cup of coffee before I start working in the gardens. We've had such lousy weather this year less than half the people who normally plant gardens are doing so this year. I have about 1000 seedlings going into the compost pile tomorrow before I leave on vacation. Our problem this year was keeping the greenhouse warm enough. I ran the heat in mid May, two weeks longer than usual.
     
  8. skruzich

    skruzich Well-Known Member

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    Yeah talk about the weather! I had set all my tomatos out for hardening process when the last "frost" date passed, and low and behold two days into the hardening off, we get 20 degree weather. You should have seen me moving stuff.

    I don't have all the nice stuff for my greenhouses, but hopefully next year I will be able to get the cooling systems. I am hoping to get 20 acres of land to move them too. Right now i am operating off of 1 acre of land here, and if i run out of room I move some of my perinnials up to my property where i am going to build my house. Don't have a whole lot of room up there but it works.
    Right now i am trying to get setup for pansies in august.
     
  9. moonwolf

    moonwolf Well-Known Member

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    I have a small greenhouse that is 10 x 12 which has pumped out a lot of transplants over the years. It has corrugated plastic and you can buy bubble plastic in rolls (like they use for packing) and there is a type of sticky glue you can use to apply this to the inside. It helps in retaining heat and also insulating from exessive UV heat coming in. It has diffuse light so is plenty for growth with this system.
    Heat is your enemy in summer, especially here in the northland with long days. By 10 a.m. usually the trays of plants need watering, and then several times in the day, but the plants grow like heck. Seedlings are started in the warm basement and grown to a stage under flourescent tube lighting until ready to put in the green house for hardening out or to continue the grown until ready to transplant to the garden. For the cooler nights where it might frost in the early spring into June, I have a circulating pump that is connected to the outside wood burning funace. The water flows through conventional copper piping with 3 'baseboard' type of heat exchanger units. Not that expensive, but well worth while if you are considering that you have a wood furnace boilder outside that heats your house and hot water too. There is no extra high electircal or hydrocarbon fuel costs, and a great way to keep your night greenhouse warmn.

    I also dabbled with a water sprinkler system on a timer like for lawn watering. This hung from the roof of the greenhouse inside to spray a cool mist (the well water is cold and this becomes very effective in mid day to cool the greenhouse and water in all one shot). All these components are readily available in places like Menard's or home hardward, or some I got from Turner greenhouse supply. I never have used fans of any sort. It would just dry things out faster. Evaporation from a misting system is high, so I had this timed to come on about every 2 hours for about 10 minutes on the days it was sunny and hot over 75 degrees fahrenheit. That's how I do it in the north and it worked. I'm often amazed at how much one really can produce for plants in a small greenhouse. For growing out plants to maturity, I would consider a hoop house or row covers.