small greenhouse project question
My wife told me no more plant seelings started inside on various window sills next year so that tells me I'm free to build a small patio-type greenhouse for a small # of seedlings. I need to get some kind of plans for the greenhouse for maybe 30 plants tops, but my real question is, assume this mobile greenhouse is built and its on my patio. I live in NW New Jersey so won't the seedlings freeze? It might be cozy in the sun but at night with no heat source it will drop big time. Thoughts?
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DoubleDogFarm
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I have a similar question. I just bought a small (5 shelf) portable greenhouse this week. It is covered in a clear, heavy plastic. It has a ventilation opening on top that you can unzip and the front unzipps also. I have my seedlings in there in the sunniest location in my house - an east, sliding glass window.
Here's my question - when would it be safe to move this outside and leave it there. It is not entirely closed - the very bottom (1-3 inches) are exposed. On cooler days I could obviously leave it all zipped up and open it up on warmer days.
I am in a suburb of Chicago and the average last frost is Mid-May.
Here's my question - when would it be safe to move this outside and leave it there. It is not entirely closed - the very bottom (1-3 inches) are exposed. On cooler days I could obviously leave it all zipped up and open it up on warmer days.
I am in a suburb of Chicago and the average last frost is Mid-May.
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Gary350
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- Location: TN. 50 years of gardening experience.
Yogas wrote:I have a similar question. I just bought a small (5 shelf) portable greenhouse this week. It is covered in a clear, heavy plastic. It has a ventilation opening on top that you can unzip and the front unzipps also. I have my seedlings in there in the sunniest location in my house - an east, sliding glass window.
Here's my question - when would it be safe to move this outside and leave it there. It is not entirely closed - the very bottom (1-3 inches) are exposed. On cooler days I could obviously leave it all zipped up and open it up on warmer days.
I am in a suburb of Chicago and the average last frost is Mid-May.
The sooner the better. When the temperature outside is above 40 move them outside then move them back into the green house at night only to protect them from frost or freeze. If there is no frost or freeze leave them out all night. I have been moving my plants in and out of the garage for 3 weeks the weather keeps changing some times the plants are out all night for a few days then inside for a few days but now that it is warmer at night they are out all the time. Just keep watching the weather and make sure they don't freeze or frost. It can frost at 38 degrees weather man said under certain conditions it can frost at 39 to 40 degrees but that is extremely rare.
I don't understand how frost is possible at 38 degrees when water freezes at 32 degrees.
I don't know about one of those shelving units protecting your plants from a frost. To me, it seems like if the temps dropped below 32, you'd loose your plants even with the plastic jacket.
Why don't you put a thermometer in the set-up and do a trial run outside without any plants in it? This way, you can see what the temperature will be in the enclosure on cold days/nights.
Why don't you put a thermometer in the set-up and do a trial run outside without any plants in it? This way, you can see what the temperature will be in the enclosure on cold days/nights.
Well, of course it matters what plants you are starting.
Some things, like eggplants should be coddled with all sorts of warmth, day and night. Now, all sorts doesn't have to mean 85°F around the clock but stunting your crop is not what you are after.
Here is a webpage and table showing Minimum Night Temperature (...°F): [url=https://www.umass.edu/umext/floriculture/fact_sheets/specific_crops/veg_bedpl2.htm]UMass, Greenhouse Crops[/url]
I used to work in a commercial greenhouse but when I set up my own backyard version, it was a lean-to against the south wall of my garage. I used an electric heater for that 1st greenhouse - probably not a very cost effective approach.
The current greenhouse is free standing and has a gas furnace. I have been very tempted to install an external insulated cover and that may go a long ways to conserving overnight heat in your greenhouse.
Since yours will be close to the house, is there a way to tap some of the air indoors to keep the greenhouse warm overnight? A connected basement window might go far enuf during the weeks of spring when you have most need for it.
Steve
Some things, like eggplants should be coddled with all sorts of warmth, day and night. Now, all sorts doesn't have to mean 85°F around the clock but stunting your crop is not what you are after.
Here is a webpage and table showing Minimum Night Temperature (...°F): [url=https://www.umass.edu/umext/floriculture/fact_sheets/specific_crops/veg_bedpl2.htm]UMass, Greenhouse Crops[/url]
I used to work in a commercial greenhouse but when I set up my own backyard version, it was a lean-to against the south wall of my garage. I used an electric heater for that 1st greenhouse - probably not a very cost effective approach.
The current greenhouse is free standing and has a gas furnace. I have been very tempted to install an external insulated cover and that may go a long ways to conserving overnight heat in your greenhouse.
Since yours will be close to the house, is there a way to tap some of the air indoors to keep the greenhouse warm overnight? A connected basement window might go far enuf during the weeks of spring when you have most need for it.
Steve
You must have double plastic to keep the heat in over night without a heat sorce. The only way to do that is have something in the greenhose that has a mass that will hold and absorbe the day heat and release it over night. It can be brick or water containers! Usually around april the water barrels are around 50 degrees inside my solar green house and keep the greenhouse above 40 even if the outside temp goes down to 25!