New Greenhouse/Cold frame

[micahmcgrath]

Just recently put the roof on my greenhouse project. I intend to use this as a summer home for tropicals and remove the side panels and wrap in shade cloth as a Cold frame for the winter. There is a window/vent in the back for the really hot days which isn't easily visible from the pictures. Still haven't put shelves up ...

The main goal of the project was to create a greenhouse which is entirely portable as I am a full time student and intend to use it on my property this coming year.

Any comments, questions, or critiques are welcome. Tell me what you think!

 

[JudyB]

I don't know how cold/hot you get in the winter, so hard to comment, also without knowing what you plan on keeping in there in winter. What are your goals for this structure in the wintertime?

 

[micahmcgrath]

I don't know how cold/hot you get in the winter, so hard to comment, also without knowing what you plan on keeping in there in winter. What are your goals for this structure in the wintertime?

It'll be in zone 7b autumn through spring this coming year. I plan to keep it as cold as possible during this time, as the winters there usually aren't very cold and I plan on storing all my non-tropicals within. However, it'll be useful then because on top of Lookout Mountain, it rains constantly during these months and my trees stayed way too wet last winter.

This summer, temps could exceed 100 on a few days, so I'll be on the watch for 90F+ days and open the door and vent.

I've never had a greenhouse but I'm presuming this makes sense to do

 

[plant_dr]

What materials is it made of? Are the bars pvc or painted white metal? If pvc, be careful how much weight you put on the shelves because at that diameter they will flex a lot and eventually break. Also if they are outside the pvc will yellow and become brittle from UV rays, also leading to damage.

 

[micahmcgrath]

What materials is it made of? Are the bars pvc or painted white metal? If pvc, be careful how much weight you put on the shelves because at that diameter they will flex a lot and eventually break. Also if they are outside the pvc will yellow and become brittle from UV rays, also leading to damage.

They are pvc. All joints are secure with screws, and shelves are duly reenforced. They walls and roof and Tuftex poly carb, which is meant to block all UVb Rays which I think are the ones that degrade pvc. Hopefully it'll hold up

 

[plant_dr]

Alright good luck with your greenhouse! They are handy to have! Be sure to show us when you fill it up!

 

[amatbrewer]

I live in a very different climate than you (hot/dry and cold/dry single digit humidity most of the year) but in case some of it might be useful, here is my learning's regarding using a greenhouse (about half the size of yours) in a similar manner.
I am using my greenhouse as a nursery in the summer (for plants needing extra care and/or protection from getting too hot/dry) and a cold box (I have a heater set to keep it just above freezing) in the winter. I have recently moved it to a place where it gets only indirect sunlight and is protected from most of the wind. I have an automated watering system that in the summer is triggered by time (what is normally about the hottest time of day) and by soil temperature, in winter it waters once every other day.

• In the summer direct sunlight can result in ridiculously high temperatures (e.g >110F on an 85F day) even with the vent and door open and a fan blowing. Even an automated misting system has not been all that effective for me (mostly results in the plants staying way too wet despite my low humidity levels). Moisture is probably a much bigger deal in your area due to your high humidity levels. I have also tried shading it with Mylar which helps, but is still not enough.
• Winter/spring direct sunlight can cause a "false spring" which could be good or bad. It can extend the growing session, but a cold snap (along with a failure of my heater) can (and has) result in damaged and dead trees.
• Finally Murphy's Law applies; I learned the hard way to to check my greenhouse often (every day if possible) even if I have to trudge through thigh deep snow to do it.

 

[micahmcgrath]

I live in a very different climate than you (hot/dry and cold/dry single digit humidity most of the year) but in case some of it might be useful, here is my learning's regarding using a greenhouse (about half the size of yours) in a similar manner.
I am using my greenhouse as a nursery in the summer (for plants needing extra care and/or protection from getting too hot/dry) and a cold box (I have a heater set to keep it just above freezing) in the winter. I have recently moved it to a place where it gets only indirect sunlight and is protected from most of the wind. I have an automated watering system that in the summer is triggered by time (what is normally about the hottest time of day) and by soil temperature, in winter it waters once every other day.

• In the summer direct sunlight can result in ridiculously high temperatures (e.g >110F on an 85F day) even with the vent and door open and a fan blowing. Even an automated misting system has not been all that effective for me (mostly results in the plants staying way too wet despite my low humidity levels). Moisture is probably a much bigger deal in your area due to your high humidity levels. I have also tried shading it with Mylar which helps, but is still not enough.
• Winter/spring direct sunlight can cause a "false spring" which could be good or bad. It can extend the growing session, but a cold snap (along with a failure of my heater) can (and has) result in damaged and dead trees.
• Finally Murphy's Law applies; I learned the hard way to to check my greenhouse often (every day if possible) even if I have to trudge through thigh deep snow to do it.

Thanks for the feedback! This is helpful information. I intend to cover the greenhouse in shade cloth in winter, probably 70% to prevent a false spring. And yes, it is already very humid inside as it is outside. Haven't gotten a reading, but I'm estimating 70-80%.

 

[amatbrewer]

Thanks for the feedback! This is helpful information. I intend to cover the greenhouse in shade cloth in winter, probably 70% to prevent a false spring. And yes, it is already very humid inside as it is outside. Haven't gotten a reading, but I'm estimating 70-80%.

I don't know where exactly you are, but I do recall during a visit to St Louis many years ago I attempted to go for a run on what looked to be a really nice day (could not understand why everyone else was inside using treadmills). I did not make it a mile because of the humidity. It felt like I was trying to breath soup!

 

[micahmcgrath]

I don't know where exactly you are, but I do recall during a visit to St Louis many years ago I attempted to go for a run on what looked to be a really nice day (could not understand why everyone else was inside using treadmills). I did not make it a mile because of the humidity. It felt like I was trying to breath soup!

I live in STL, and that is a 100% accurate description - especially at this time of the year. Should I be aware of any fungal issues this could introduce? Of course, in autumn to spring I'll be using the structure to prevent excess moisture...

 

[penumbra]

I think you did a nice job but you really should have used pvc conduit (gray) as it is uv resistant. I built an overwintering house of pvc some years ago and I believe it only lasted two years before the pvc became brittle and broke apart. Still, your little house is much nicer than mine was.

 

[micahmcgrath]

I think you did a nice job but you really should have used pvc conduit (gray) as it is uv resistant. I built an overwintering house of pvc some years ago and I believe it only lasted two years before the pvc became brittle and broke apart. Still, your little house is much nicer than mine was.

I hope mine lasts a bit longer .. either way the frame was only about $100 to construct. What did you use to cover yours?

 

[Carol 83]

I did not make it a mile because of the humidity. It felt like I was trying to breath soup!

Welcome to my world

 

[penumbra]

I hope mine lasts a bit longer .. either way the frame was only about $100 to construct. What did you use to cover yours?

I used white crop cover plastic because it was only for winter storage. I hope your plastic sheets offer more uv protection.

 

[micahmcgrath]

I used white crop cover plastic because it was only for winter storage. I hope your plastic sheets offer more uv protection.

Hoping so too. Thanks for your input

 

[Forsoothe!]

Window screening works well. I have screen panels the same dimensions as my roof panels and they just lay on the glass, but my roof panels open 6" at the peak and I have a door that is left open in daytime. Thee air needs to enter low and vent high, continuously.

 

[atlarsenal]

The rabbit is already figuring a way to get in!

 

[micahmcgrath]

The rabbit is already figuring a way to get in!

He's a sneaky one ..

 

[JudyB]

You might want to take a look at a material called solexx.