Bobberman
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Once a tomato seed sprouts what is the perfect temp?

If I had a grow chamber that was set at 75 or higher and a tomato or pepper sprouted in less than week how will low temperature outside the grow or sweat box effect it after it sprouts? I am talking of temp at between 32 and 40 at night and a little higher in the daylight! Once it sprouts is the light the most important thing or the temp or both? Will the low temp make the plant stronger in the long run as long as there is alot of light in a greenhouse? Slowing the stem or leaf growth rate down by a lower temp could give a better root growth or not?

I noticed when plants grow too fast they are thin so I am wondering what is the perfect temp after sprouting?

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gixxerific
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32-40 is pretty cold for tomatoes. After germination light is the most important thing than comes the moderate temperature.

If you are seeing thin/leggy plants it could be your lights are too far away. Keeping light close 4 6 inches is a good distance. Another thing to beef up your beefmaster (pun intended) is to put a fan on them every day for short times. This will makes the plant grow thicker due to survival instincts to protect themselves from said wind. The fan can also cure many fungal problems.

Bobberman
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My plants are not leggy but very nice but grow slow because of the low temp at night! I guess they have to be in 34 to 40 degree temp every night and 90 degree temp all day! I guess they become stronger that way what do you think?

cynthia_h
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Most of us on this forum perform our experiments personally and then report our results. Theoretical questions help us design our experiments, but simply asking questions and discussing *possible* answers aren't very helpful when one is trying to grow food.

Not in my world, anyway.

What temps have you experienced when growing your tomatoes?

Cynthia H.
Sunset Zone 17, USDA Zone 9

Bobberman
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As I said my greenhouse is in the low 30, at night from the march to the middle of april. For the last 4 years I have grown tomatoes and peppers under those conditions with little problems! I want to know what others experience that is why I ask! Everyone does not have a heater in their greenhouse especially if its bigger than just a 6 by 6!

wordwiz
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cynthia_h wrote:Most of us on this forum perform our experiments personally and then report our results. Theoretical questions help us design our experiments, but simply asking questions and discussing *possible* answers aren't very helpful when one is trying to grow food.

Not in my world, anyway.

What temps have you experienced when growing your tomatoes?

Cynthia H.
Sunset Zone 17, USDA Zone 9
Huh? A simple question, a semi-berating from a mod. Not what I am use to reading in this wonderful forum! But to answer your question, from the low 20s to about 90 degrees. The plants were under a cotton canvas, at least until the middle of May or so.

Mike

Bobberman
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Thanks Mike! I plan on have a sweat chamber in the future which should solve my low temp at least to help the seeds start! I do have trouble getting the seeds to start t that low night temp.especially tomatoes and peppers!

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Kisal
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I think with sprouting seeds of warm season species like tomatoes and peppers, the soil temperature is more critical than the ambient air temperature. That has been my experience, anyway.

Oregon is notorious for its occasional long, wet, cool spring weather, that sometimes lasts into July. If I sow seeds outdoors when the soil is still cool, they just rot. If I start the seeds indoors and set the plants out while the soil is still cool, they just sit there and do nothing, until the sun is able to warm the soil to the right temperature.

I'm inclined to agree with mikestuff that 50º is about the lowest temperature at which I've ever had tomatoes succeed. I've never had cool temperatures improve the stockiness or strength of my plants. My considered opinion, in fact, is that stressing plants by exposing them to low temperatures would be much more likely to weaken them, and perhaps make them more susceptible to disease later on. Plants that have been stressed, whether by too low or too high tamperatures, lack of nutrients, or lack of or too much water usually are less successful at resisting attacks by insects, bacteria and viruses. JMO. :)

Cirtes
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Based on published science (university agriculture classes) root growth occurs between 50 and 80 degrees for nightshades. 65 degrees is optimal.

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Gary350
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I sprout tomato seeds in the house temperature is 75 deg in the day 70 deg at night. I keep plant trays in plastic trash bags to hold moisture. Plants are usually up in 3 days. Once plants are up all the trays go outside in the weather as long as the temperature is above 40 deg F. Plants come inside at night and out again during the day. Plants are ready to transplant to the garden in about 30 days.

Bobberman
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I have a few thousand tomato plants now some a foot tall. My temp in feb and april when I started the seeds was as low as 30 at night but did not hurt the small seedlings. I think it tuffend them up. They were slow but I did not loose any! My peppers took a month to come up but they are about 6 inches now!



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