Has anyone ever grown seedling in a cold garage?

plainolebill

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I have a 2x4 closet in my attached, uninsulated garage I'd like to use as a mini greenhouse to get some plants started that aren't available locally. I'm thinking of tomatoes, peppers and eggplant varieties that we have grown in the past but have been pushed aside for younger sexier varieties.

I live in the Willamette Valley Oregon, pretty mild 30-50 degrees usually in the winter but can occasionally get much colder. The garage is usually a little warmer but not much.

I'm thinking of using some light insulation covered with cast off mineral based ceiling board. I'm going to buy a grow light and maybe line the space with foil to reflect light all around.

My big questions are heating, ventilation, how far the light should be from the plants at various stages of growth. I think the primary users of this stuff is pot growers but that's not me. If anyone has any knowledge of this that they can pass along I'd appreciate it.

Thanks, Bill
 

digitS'

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Hi there 'Bill !

This is a super question for @SprigOfTheLivingDead who grows plants in his basement through the winter.

I have only a very little experience with supplemental lighting. I believe that this is what @catjac1975 does each and every winter. (Others start transplants under lights. You might think that after a lot of growing seasons, I would have experience with that but I tend to gravitate to South Windows and Exposures, instead.)

I did a little driving South(west), recently. Enjoyed being in Portland for Christmas. It has been a long time but I used to be down there, at least, a couple times each year.

Steve
 

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digitS'

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Ya know, @Crealcritter 's indoor growing may not be all that much warmer than what you are thinking of, 'Bill:

 

Ridgerunner

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My big questions are heating, ventilation, how far the light should be from the plants at various stages of growth.

I'll include this photo to give me something to reference, plus we often like photos.

Grow Stand.JPG


Heating - The plants you mention are generally warm weather crops. The seeds require a minimum temperature to germinate. Insulation will not give that to you where you are. The optimum soil temperatures for germination for those plants is probably 70 to 85 degrees Fahrenheit. If you get much below 70 germination will be slow, erratic, or may not occur. That plywood box is filled with Christmas lights, I regulate soil temperature by how many bulbs I have on. If I were starting over I'd get a heating pad specially made for this that can be regulated. You can probably get a small thermometer that sticks in the soil at a garden center. It doesn't have to be that accurate.

I don't know what effect air temperature has on how they grow, maybe soil temperature is more important. I'm sure it has an effect, just not sure about how much. You may want a heat source in there but in that small of a space I'd think you would not need that much, especially if you insulate it.

Ventilation - I don't know. Plants use Carbon Dioxide and give off oxygen. I'm sure you want some ventilation but not sure how much is required. I'd think not a lot.

Another issue is damping off. You need moist soil for the seeds to germinate but if the soil stays too damp a mold or fungus can grow that will kill the seedlings. To dry my soil surface I use a small fan to provide a gentle breeze and try to water from underneath. You may have to go online to find a small fan. I could not find a small fan in winter but had to wait until summer when they were available. It's not in that photo.

Light - The general recommendation is to keep the lights about 2" above the top of the plants. This can be a challenge, some tomatoes grow faster than others, let alone the difference between tomatoes, peppers, and eggplant. I try to keep the light above the tallest plants. That's what those chains are for, to adjust the height of the lights. Give yourself a lot of headroom so you can adjust the lights. You see where I had to splice onto the legs to raise this. I'll admit to a sacrilege. If my indeterminate tomatoes get too tall and it's not time to go outside, I prune them back to just a couple of leaves. They will send out a sucker from the leaf base that will make a new plant. I don't do that with my determinates, but then I hardly ever grow determinate tomatoes. I don't do that for peppers or eggplant but I've never had to.

I found it extremely helpful to reflect light from the sides. This helps keep them from getting tall and spindly. That's what the paper is for. You might want to paint your walls a bright white.

You will be using water in there. Electricity and water is a dangerous combination. So be careful how you set it up and make sure you have water containment under it.

To me it sounds like a great set-up. I'm not sure when you can go outside with them but I generally start them about 2-1/2 months before a normal time to transplant. That way I'm ready if the season is unusually warm early.
 

so lucky

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I have regular shop lights set up in my basement, on chains for height adjustment as the plants grow. 2 sets of 2-bulb fixtures, 4 ft long. I buy a couple of bulbs every year to rotate out a couple.
One thing I have found is that you need air movement around the plants to make the stems sturdy and to avoid damp-off, as Ridge said. I use a small fan that is on the same timer as the lights. Usually about 16 hours on, 8 off. The temp is around 65. Plants that require warmer temps for germination, I sow them in small "flats" (usually plastic berry boxes), cover the planted containers with saran wrap and put on top my fridge, checking every few days for sprouts. Once they start to sprout, they need to be unwrapped and put under the lights, about 2" from the lights.
I use blocks of wood, wide pots, bricks, etc., what ever I have, to elevate the plants as they grow, adjusting the lights to accommodate the tallest plants. Of course, I am always putting some of the plants in larger pots or six-packs as they grow.
One word of advice: Those jiffy pots and peat pots look like they would be really good for the plants but most people who use them are not happy with them. Too wet, too dry, peat wicking the moisture out after you plant in garden, plant remains pot bound by the netting, other complaints.
Good luck, happy growing.
 

digitS'

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Here is some temperature information on ornamental plants from Michigan State U. These are ornamentals and this is for greenhouses but you can see the differences in expectations.

Capture.JPG


Notice that there is quite a bit of difference from one species to the other, along with the difference in growth in the temperatures, only varying about 5°f.

And, this is important. Note that the light is the same across the board. This is probably a fairly optimal level and was supplemented with electric lighting. What I didn't find with a quick search was differences in growth with the TWO variables of light and temperature. That would be a bit complex. Realize that you cannot push growth with warmth under low light conditions. To do so will result in weak leggy seedlings.

Steve
 

catjac1975

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Hi there 'Bill !

This is a super question for @SprigOfTheLivingDead who grows plants in his basement through the winter.

I have only a very little experience with supplemental lighting. I believe that this is what @catjac1975 does each and every winter. (Others start transplants under lights. You might think that after a lot of growing seasons, I would have experience with that but I tend to gravitate to South Windows and Exposures, instead.)

I did a little driving South(west), recently. Enjoyed being in Portland for Christmas. It has been a long time but I used to be down there, at least, a couple times each year.

Steve
More important for most seeds is bottom heat. They need light of course, but added heat will give you the best results. A good heat mat will last a long time.
 

Prairie Rose

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Hello! I overwinter houseplants and start my seedlings on a cheap indoor greenhouse I fitted an LED grow light to. I keep the whole unit in an unheated room of my house...the heating vents are closed in there, but it does get some residual heat from the rest of the house. I had spotty results last year, but this year I am going to add a small fan to encourage ventilation and a couple of heat mats to help things sprout faster.

I think your idea sounds like a good idea...it doesn't hurt to try!
 
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