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alohamillion123

Cool or warm lights for tomatoes?

alohamillion123
19 years ago

Hi, I did a search of the archives and found different opinions of what types of lights to use. Do I use two cool lights or one warm/ one cool for starting tomatoes? What is the best choice considering my growing conditions of:

growing in our basement (dark and cool) using a fan for ventilation; haven't decided on what type of seeds yet.

Any info greatly appreciated =)

Stacey

Comments (8)

  • watergal
    19 years ago

    For seed starting, cool white is enough and I think a bit cheaper than warm. I use a mix of half cool and half warm for all my plants since I grow a lot of things along with the seedlings.

    Tomatoes will not like germinating in a dark cool place. They need warmth and light. Can you supply bottom heat somehow - put the trays on top of an appliance that's warm on top, like a fridge or TV, or buy some heating mats designed for starting seeds?

  • alohamillion123
    Original Author
    19 years ago

    Thanks Watergal =)

    Yes, I can buy some heating mats somewhere for them. (Any suggestions on WHERE to get these and what they will run me?) I think our basement will be in the 65' range if I open the heat duct. At what temp is optimum? So do I understand you that cool white is okay but a mix of both is better? They are Free After Rebate at our hardware, so I plan to buy several of both if need be so whatever works best is what I will use.

    Again, thank you for the help and sorry to give you all these questions again! I have never done this type of seed starting before/ have always wanted to/ so everything is all new to me =)

  • maineman
    19 years ago

    Stacey,

    Cool white is fine for starting the seedlings. If you plan to grow them to the blooming stage, you might want to add some warm white or get Sylvania Gro Lite tubes, which have a good mix of red and blue, which results in a hideous purple light, but the plants love it. Last year I used mostly 4100K cool whites (not very cool when compared to really cool whites like 6500K). I got the 4100K Philips T8s from Home Depot in builder's paks of 10 bulbs for $19.99, so the price was right.

    I am adding a few shelves to my growing setup this year and I think I will invest in some of the more expensive Gro Lites because my shelf space is rather limited and last year several things came to the blooming stage with a mix of 4100Ks, 3500Ks and a few 3000Ks. I set out tomatoes, peppers, watermelons, and zinnias with their first blooms on them, so it might be worth it to have better bulbs this time. Of course I will re-use last year's bulbs as well. Incidentally, I overdrive my bulbs for about 50% more light according to Zink's instructions and I also use fans for a little artificial breeze.

    MM

  • watergal
    19 years ago

    I was looking through some garden catalogs last night, and about 77 degrees is optimum for starting tomatoes. A heating mat will run a bit warmer, but that's OK - they like warm roots. Once the plants get to be a couple inches, you can remove the mat.

    Cool white tubes are fine for growing anything when you just want leaves, not flowers. The warm white spectrum helps to encourage blooms. Since your plants will be too little to be blooming, it doesn't really matter to you - get whatever is cheapest.

    You may have to get heating mats online or from a gardening catalog. Here's an example for you. I've never needed one - my rooms run warm. This seems to be an average price and it's a reputable retailer I've used.

    Here is a link that might be useful: Park's Seeds heating mat

  • KayLakeMan
    19 years ago

    I use an old heating pad, the small kind you use for your back after the first hard day in the spring time garden. Covered with some plastic to protect it from moisture, turned to the lowest setting and plugged into the timer.

    Works for anything requiring a little heat in the basement.

  • bobb_2002
    19 years ago

    Heating mats are nice but not really necessary. If you leave the lights real close and don't turn them off you will find the soil gets quite warm. After most seeds are up you can put the lights on a timer, Seedlings like cool night temperatures so they don't get too spindly, and 60 or 65 is not too cold. If your basement is really cold (50 or so) then heating pads will be essential.
    I started some tomato seeds near the furnace at 80 degrees with no light and some varieties were completely unfolded in 3 days, so I had to get them under lights real fast before they got leggy. Now they are in the garage which gets about 55 at night and the lights keep them quite warm when they are on.

    Bob

  • kdjoergensen
    19 years ago

    If you are starting the plants indoors with objective to transplant outdoors in summer, then cool whites are all you need.

    65F is fine for tomatos.

  • SLeepyHead
    19 years ago

    I grow my tomatoes in my room actually, which stays at about 70-72 degrees at all times, might drop a little colder when im not at home. My entire light setup is in there. Is it better to move them to a colder spot at night while i sleep, when the lights are off, then back indoors in the morning to go under the light? I don't want them to get spindly. Thanks.