Hi everyone, I have recently built a 15’x40’ greenhouse which is heated and dehumidified to grow plants this winter for my landscaping company. I will also probably try to grow some auto-flowers in it this winter. I have some lights ordered since I live near Portland Oregon where the winter days are typically short and cloudy so there isn’t a ton of natural light. I’m hoping I can get some advice from an experienced greenhouse grower and cannabis growers are some of the most experienced so I am asking here.
Most of the greenhouses growing Recreational here that I have seen out in the local countryside have a completely white covering and they are relying entirely on artificial light which seems to make sense for photo period plants.
However, I am mainly trying to get vegetative growth (except for my auto flowers which will flower regardless). I have a dual wall inflated outer layer which insulates nicely but I am looking at getting some panda plastic on an inner layer to reflect light back to the plants and so my neighbors don’t have to look at a huge light tube out their windows at night. Essentially I am using the plastic for the opposite of light dep and trying to get as much light to my plants as possible.
my main question is if I am only doing vegetative growth then during the daytime or at least on the sunny days we get is it worth opening the panda plastic to capture some of that sun light for photosynthesis as well as trapping solar heat? or will I end up losing more of the light from my grow lights than I will gain from winter time sun light?
my one other question is the plastic is serving a secondary function of adding a third wall of insulation to reduce heating costs. Will the white side of panda plastic reflect infared heat to help reduce heat loss or should I really be looking at a silver surface for that? My main concern with Mylar is that it won’t hold up to being rolled up and down like the plastic would so I’m hoping the panda plastic will at least offer a decent amount of IR reflecting.
thanks
Most of the greenhouses growing Recreational here that I have seen out in the local countryside have a completely white covering and they are relying entirely on artificial light which seems to make sense for photo period plants.
However, I am mainly trying to get vegetative growth (except for my auto flowers which will flower regardless). I have a dual wall inflated outer layer which insulates nicely but I am looking at getting some panda plastic on an inner layer to reflect light back to the plants and so my neighbors don’t have to look at a huge light tube out their windows at night. Essentially I am using the plastic for the opposite of light dep and trying to get as much light to my plants as possible.
my main question is if I am only doing vegetative growth then during the daytime or at least on the sunny days we get is it worth opening the panda plastic to capture some of that sun light for photosynthesis as well as trapping solar heat? or will I end up losing more of the light from my grow lights than I will gain from winter time sun light?
my one other question is the plastic is serving a secondary function of adding a third wall of insulation to reduce heating costs. Will the white side of panda plastic reflect infared heat to help reduce heat loss or should I really be looking at a silver surface for that? My main concern with Mylar is that it won’t hold up to being rolled up and down like the plastic would so I’m hoping the panda plastic will at least offer a decent amount of IR reflecting.
thanks
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