WINDY
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Best Light for Tomato Seed Germination?

Does anyone know what the right kind of light to use for
germinating Tomato seeds indoors?

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Gnome
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WINDY,

They do not need any light to germinate. Once they begin to break the surface of the soil I use fluorescent lights as close as you can get them without overheating the plants. Isn't it a bit early to be starting these? :wink:

Norm

grannygreenthumb
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I agree with Norm - 4 foot shop lights with standard fluorescent bulbs suspended no more than 2" above the tops of the plants is all you need once the seeds germinate. I keep mine on 16 and off 8 hours a day and turn the trays daily as the light is stronger in the center than at the ends. Some recommend 24 hours a day but I have never found that to be needed.

Don't know where you live but you only need to start your plants 6-8 weeks before transplanting outside date. Much sooner and you end up with plants that are so large they don't tolerate transplanting at all well.

TZ -OH6
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You can go higher than 2" but I would not go higher than 12" because you'll be wasting light. It also makes it easier to work with the plants. Reflective material along the sides and under the pots helps boost light, anything white, or aluminum foil works well.

Another option is to use a shoplight to supplement direct sun windowlight, which is much more intense. If you do it that way you will have to raise up the fixture to avoid shading the pots.

FredDuggan
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Get a small show light. 20 watts is good. Get them close but just make sure its not to hot. You should be able to keep the back of your hand their without it getting hot.

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hendi_alex
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IMO, three things are critical for successfully starting and growing the best tomato seedlings indoors. First you want to have bottom heat. That can be rigged by placing a metal tray over an incandescent light bulb or using some kind of heat mat, or simply setting the container over any 70-75 degree surface. Bottom heat will insure quick germination with high germination rate. Secondly, you need to provide as much sunlight as possible but augment with 12-14 hours of artificial light. When I'm only starting a few seeds in one pot, I use a 15 watt compact florescent bulb placed within a couple of inches of the top of the seedlings. The combination of sunlight and artificial light will give you stocky, thick leaved plants. The third thing which helps give great results, IMO, is to set the plants outside in the direct sunlight but in a sheltered location, as soon as possible after germination and any day in which the temperature gets above sixty degrees. This is not absolutely necessary, but will help you grow dark green, thick stemmed, fleshy plants that are already hardened to the sun and the wind. These tough plants will not even slow down when placed in the garden in the warm spring soil.

TZ -OH6
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Good point about the bottom heat. I place the seeded pots under my computer table where heat accumulates, some people put them on top of the refrigerator etc. The increased temp (80-90F) is most beneficial for quick germination so after sprouting you can move the pots under lights at room temp. Some say that reduced heat (65F) during seedling growth helps prevent leggy seedlings, so I don't worry about growing at room temp.

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hendi_alex
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I started my first set of seedlings about 3 weeks ago. Five seeds were placed in a single three inch pot, but as soon as the plants developed true leaves, each was moved to an individual three inch pot. In a couple more weeks, the seedlings will be stepped up to four or five inch pots. The plants will be placed outside in the sunlight and air on any day that the temperature exceeds sixty degrees. On relatively cooler days they will be placed outside in a cold frame. On relatively warmer days they will get full exposure. The plant containers will continue to be stepped up in size until by early spring the plants may be in three to five gallon pots. Two plants will likely go in the ground and two will be planted in 25-30 gallon containers until maturity. The plants should be loaded with blooms and tomatoes by late March or early April, with the first ripening in late April or early May. Most gardeners get their first tomatoes here in zone 8 around the first of July or perhaps late June.

Here are a few photos of my improvised set up.

Tomato seedlings, about three weeks old, makeshift light. The plants appear to be thick stemmed and vigorous getting both greenhouse filter sunlight, plus about 14 hours of supplemental light.

[img]https://farm4.static.flickr.com/3445/3221967435_a040fb7a14.jpg[/img]


Plants are located on a shelf directly over the heat source. They are sitting in a bottom tray with pebbles and water to combat the dry heat. The greenhouse stays very humid however.

[img]https://farm4.static.flickr.com/3123/3221967721_a1fa86b9bb.jpg[/img]

The plant tray is sitting on sheet aluminum to serve as a heat deflector, but also as a conductor to provide gentle bottom heat.

[img]https://farm4.static.flickr.com/3455/3222821148_12254dbb25.jpg[/img]

In the next few days, I'll plant five 'Sweet cluster' seeds, and soon after will start the seeds for my slicing varieties, plus will start egg plant and pepper plant seeds at that time. Last, in early March will start a few early cucumbers and squash, to gain a couple weeks on the harvest time. I find that these early plants are not as hardy, and don't have the longevity of later plants, so a succession of plantings is really helpful for keeping a steady stream of fresh garden produce from April through November or December her in zone 8.

Alex

Learn & Grow
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As the initial response to your question was correct... to germinate tomato seeds light is not required warmth is. Although fluorescent shop lights may work OK with a grow light bulb a much better and affordable option is an LED grow light. LED lights in the nursery industry have come along way. LED's have come of age. They are hi-performance/professional quality. In fact compete against lighting that costs thousands of dollars for pennies on the dollar.

For the home grower hobbyist I would highly recommend bottom heat and LED lighting. Here are some online sources -

[url=https://www.amazon.com/s/?_encoding=UTF8&keywords=seed%20heating%20mat&tag=thehelpfulgar-20&linkCode=ur2&camp=1789&creative=9325]https://www.amazon.com/s/?ie=UTF8&keywords=seed+heating+mat[/url]

Good luck!

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Gary350
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I germinate seeds in the dark.

I wait until the weather is warm enough to put the plants outside in the sun during the day before I germinate any seeds. I plant seeds in composted cow manure I buy in bags. Fill trays, plant seeds, put the trays inside of a plastic garbage bag to hold the moisture. Keep it room temperature seeds will be up in 4 or 5 days.

Once seeds are up keep a fan blowing on them inside the house it keeps them from getting stem rot. Put them outside during the day in the sun. Water the plants from the bottom. In 2 to 4 weeks they will be ready to plant in the garden.



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