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Indoor subsistence growing

Posted by Natures_Nature 5 OH (My Page) on
Sun, Dec 15, 13 at 16:54

Hello

I would like to have enough greens to eat at least a normal sized salad everyday. I never tried to grow inside like this before. I do start seeds and have all the lights(just fluorescent shop lights), i just never really had a indoor garden. I was hoping for you guys who actually do this to chime in. Is it unrealistic? Anyone out there do something similar?


Follow-Up Postings:

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RE: Indoor subsistence growing

I grow lettuce and the like in the winters, so no it is not unrealistic and am hoping to harvest a winter melon this year.

Question is if you have enough lights and/or willing to purchase enough to accomplish this goal.

If I can be any help please let me know.

SCG


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RE: Indoor subsistence growing

Yes, if you have experience with growing leafy greens indoors, you are of much help. How much lights/plants/space do you need to yield a medium size salad everyday?


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RE: Indoor subsistence growing

Well, starting with what you would consider a medium sized salad, and what greens you like. I would personally think that you would be best growing essentially twice what you would eat in a week, so you can harvest half the leaves of a plant and give it a week to recover. I am going to roughly say with my household, a salad might require one or two types of lettuce, a spinach, and maybe some chard. You may be able to get away with good growing conditions with seven or eight plants each, so maybe thirty total. For leafy greens, you will do just fine with the kind of generic T8 shop lights from a big box hardware store hung 18 to 32 inches above a shelf. You can cover a shelf effectively with two double bulb fixtures. Ideally you want daylight 6500k bulbs, but they will be fine with the warm spectrum that comes with the fixtures. That gives you about twelve to sixteen square feet of good growing
space. For reference, you can divide the space into basically three sections that each have a five gallon pot and two two gallon pots. You could fit five lettuce into each five gallon, and a pair of spinach in the twos. Then do a second shelf of three chard in six three gallon pots.

I think that you could come pretty close to what you want with two shelves of four total fixtures, about 160 watts per shelf, total upfront cost maybe 80usd. You could arrange them differently and probably fit the same plants under a single metal halide 250w fixture, if you build essentially stadium plant seating. Fluorescent fixtures are good for leafy greens, particularly if you are willing to screw around and play with individual plant height to keep the tops all close.

You will want to put an oscillating fan across the room and keep the room cool. You will also probably need to talk to your plants to keep the CO2 rich in that room if you don't want to mess with real exhaust systems. Humans generate plenty to keep an indoor garden thriving.

It's all back of the envelope math, but I think it may come close to the kind of production you want and be tasty and satisfying to watch grow.


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RE: Indoor subsistence growing

Thanks guys! So it does seem realistic..

About lights:

I have five shop lights that fits four fluorescent tubes. The tube bulbs are a 50/50 mix between 3000 lumen, 4500K cool white tubes, and 2500 lumen, 6500K warm tube lights.. So there would be two of each bulbs in each shoplight, and i have five shoplights total. I have a five tier shelf right by a south window, i hang the shoplights off each tier, there is about 1 ft between each tier.. Each tier has one shoplight(it will only fit one, plus one is more than sufficient).. So each tier gets roughly 11,000 lumens, 20,000 k. I plan on using a fan and some reflective material, maybe mylar, if i can afford it..

So i am using 11,000 lumens,20,000K covering a 8 sq ft area. So a little more than 1,000 lumens a sq foot, or 2,000K.. I heard for vegetative growth you should have at least 2,000 lumens every sq ft..i know ill be fine now, but i wonder if i could be a lot better..


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RE: Indoor subsistence growing

Reflective material would work, but is likely overkill. Fluorescents in the blue spectrum are fairly ideal for leafy greens because they encourage vegetative growth with short internode spacing. I would not bother buying new bulbs, but you don't really need the reds because you are not flowering. Likewise, you want to encourage vegetative growth with plenty of darkness and coolness. It's just a matter of whether you can fit enough plants for that much continual harvest. You may be able to fit more long window boxes into that area, which greens share very nicely. Estimate a gallon per plant, but plan for larger pots with more plants so watering can be more even.


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RE: Indoor subsistence growing

Sorry I didn't get back faster.

You need to clarify salad size to make the appropriate comparisons. I grow lots of lettuce under lights and get 18 plants per 2'x4' T5 HO fixture (8 bulb) that gives us enough to have fresh lettuce everyday. This is on a 6" spacing per plant.

I have to run but can give more tomorrow.

SCG


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RE: Indoor subsistence growing

Incidentally, you might consider tossing in a few other random non-standard greens, like nasturtiums. Even beets will give a lot of tasty greens and can be crammed into small spaces. I have had great luck getting both of those bushy and lush in tiny containers under T5s.


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RE: Indoor subsistence growing

"Likewise, you want to encourage vegetative growth with plenty of darkness and coolness"

Now i heard of coolness and lots of light for leaf growth, but darkness? I know some people grow plants in 24/7 light, just for leaf growth. What would the darkness do? Curious.. I will look for other more nutrient dense palatable greens, thanks.


"You need to clarify salad size to make the appropriate comparisons. I grow lots of lettuce under lights and get 18 plants per 2'x4' T5 HO fixture (8 bulb) that gives us enough to have fresh lettuce everyday. This is on a 6" spacing per plant."

Salad size as in size of a dinner plate, say 3-4 cups of coarse chopped lettuce, everyday.. So you grow 18 plants, light fixture is 8' sq, how big is your growing area? How much fresh lettuce do you get, a few leafs just for a sandwich, or?


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RE: Indoor subsistence growing

Hi Natures_Nature,

I think when Mister.Guy mentioned “plenty of darkness” he was probably referring to the photoperiod of long-day plants. Lettuce for example is a long-day plant, meaning that if the daylight (or your artificial lighting) is over about 10 or 12 hours it will tend to flower. Of course, you don’t want that to happen to your lettuce :-) So, for growing lettuce, you want short days and long nights (plenty of darkness). You control that by having your lights on for less than 12 hours a day (10 may be better). Heat also encourages flowering, thus his suggestion for “coolness”.

Hope this helps,

Art


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RE: Indoor subsistence growing

Art has it spot on. Salad greens grow best in perpetual early spring and seed in the summer, so you would want to imitate great spring conditions. 10/14 or 12/12 blueish lighting with temperature differences between day and night if possible and cool growing conditions. The rest is just cramming as much light into the smallest space you can, and your four bulb fixtures will be sufficient.
Kale, spinach, and even broccoli will veg well and provide contrasting flavors in a container garden. You can treat the whole space as a small square foot garden as far as figuring out what you can fit in your space.


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RE: Indoor subsistence growing

." Lettuce for example is a long-day plant, meaning that if the daylight (or your artificial lighting) is over about 10 or 12 hours it will tend to flower. "

Now i understand... This would work out perfectly. The shorter days means less light, less light, less electric and heat.

"treat the whole space as a small square foot garden as far as figuring out what you can fit in your space."

Brilliant idea!!! It would make it too easy!

So what do you guys think about yielding: Salad size as in size of a dinner plate, say 3-4 cups of coarse chopped lettuce, everyday.. How many plants would i need roughly?


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RE: Indoor subsistence growing

While I don't disagree that lettuce likes shorter days I run my lights 15hrs a day with no problems of it wanting to bolt. I do keep my temp down around 60F. If I don't get too aggressive when picking I have been able to get 6 weeks out of plants possibly longer but the next sowing was ready.

How many plants you need is going to depend largely on the variety. If growing Grand Rapids you might need 4-6 plants but would need 6-8 of lambs.

We eat a couple large salads each week, I would guess 16 cups or so plus enough for sandwiches and the like. That is with18 plants a sowing.

Good luck


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RE: Indoor subsistence growing

While I don't disagree that lettuce likes shorter days I run my lights 15hrs a day with no problems of it wanting to bolt. I do keep my temp down around 60F. If I don't get too aggressive when picking I have been able to get 6 weeks out of plants possibly longer but the next sowing was ready.

How many plants you need is going to depend largely on the variety. If growing Grand Rapids you might need 4-6 plants but would need 6-8 of lambs.

We eat a couple large salads each week, I would guess 16 cups or so plus enough for sandwiches and the like. That is with18 plants a sowing.

Good luck


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