Designing budget greenhouses (light assist) for 2 crops a year in Maine!

ive been recently mulling over design and buildout parameters for greenhouses on our small property to max out my caregiver plant counts (78 flowering plants). the idea would be to use a hoop bender jig and make some 12ft-16ft wide hoop houses using double inflated poly coverings for insulation. for simplicity and laziness id like to keep them single row of plants down the middle and each end wall big enough to fit my Kubota M5-111 through. if i keep them as narrow as possible the better (leaning towards 12ft wide) but using tall sides so i can have at least a 9ft x8ft wide opening on both ends. ill be able to use a tiller and run straight down the middle each crop cycle to amend the soil. Ive never built a greenhouse before and these certainly wont be commercial grade expensive setups. im thinking maybe 4 greenhouses each housing 20 plants, spaced 6ft center to center in a stripe right down the middle of each GH. each plant will have a 240w Quantum Board style light over it for light assist only. As many people know Maine has drastic swings in seasons which means a summer crop might see outdoor temps as high as 90s during the day and winter crops might see temps as low as -10F. the GH environment will need to be able to keep temps cool enough during summer and warm enough during winter crops but the RH not having massive swings from like 30% to 70% during each exhaust event. any ideas and advice would be greatly appreciated and cost is a vital concern. we plan to set this up without massive upfront buildout costs. ill be doing all the work and build myself. Im not sure if i want to go dep the first few runs, the systems are complicated and i think i could just time the long summer light cycle for the veg time on a summer crop. winter is not a problem since after I would chop the summer crop (october-november) the light cycle will always be less than 12 hrs. i would time the summer crop June to November, winter crop December to May. The light cycle in Maine would allow be to not have to build a light dep setup and i could simply use light assist during veg.

Man that is one long paragraph
Two things strike me
1 I see no heat source ie...furnace

2 light from winter sun isn't as strong so your plants will outstretch a hoop house

The idea is solid but a hoop house in winter isn't going to do what you think IMO

Imo heat IS the difference between a hoophouse and a greenhouse

Herb & Suds said:

Man that is one long paragraph
Two things strike me
1 I see no heat source ie...furnace

2 light from winter sun isn't as strong so your plants will outstretch a hoop house

The idea is solid but a hoop house in winter isn't going to do what you think IMO

Click to expand...

it will be a full blown green house using 1-3/8 top rail bent hoops, probably 10-12ft high in the center.

i havent decided on heat source yet. but im thinking either cheap pellet stove, propane or even kerosene heaters direct vented.

Poop have you checked out bootstrapfarmer.com

Im seeing 20x80 kits under 2g

Ive been hoping to build one myself by next season. May go this way verse bending depending where material prices are at then

ya but honestly 20ft wide is bigger than i want, id like to keep them under 12ft wide just tall enough to fit my tractor (its a bigass tractor lol) and not overly wide so i can run 4 of them along side each other with the space i have on the property. 20 footers would take up twice the width if im only utilizing a single row down the middle for planting.
im not interested in having thousands of pounds of metal poles shipped to me via freight, the cost is twice the price of the kit itself just to get them shipped. its much cheaper for me to buy a bender and bulk top rail and bend the hoops myself.

Ya freight is a mutha, theres dif sizes but I hear ya. For some reason I was thinking they were a Maine based company

theyre out of texas. the cheapest solution from what ive see is going to be bending my own hoops

Ya i guess if theres no place local ill end up doing the same. Good luck

I really like the little china diesel heaters for heat but i dont see any affordable ones over 8kw. i might have to run a few per greenhouse but they look super efficient.