Ideal/tolerated temperatures

[tam91]

It seems that most of my tomato plants shut down for a while with the really hot temperatures. So this led me to wonder re. daytime and night temps:

What is the ideal temperatures for tomatoes?
What will they tolerate and still produce?
What temps cause them to shut down, but not die?

Not that I can do anything about it of course, but I am curious.

[Stepheninky]

Originally Posted by tam91

It seems that most of my tomato plants shut down for a while with the really hot temperatures. So this led me to wonder re. daytime and night temps:

What is the ideal temperatures for tomatoes?
What will they tolerate and still produce?
What temps cause them to shut down, but not die?

Not that I can do anything about it of course, but I am curious.

If I remember reading correctly in a pub on controlling greenhouse climate for best results for tomatoes it was 55 deg F night temps and 75 - 85 Deg F for daytime temps.

Though I agree it is not practicable just what I remember reading

As for the other two questions I would think it varies a bit in relation to what variety you are growing.

[habitat_gardener]

Originally Posted by Stepheninky

If I remember reading correctly in a pub on controlling greenhouse climate for best results for tomatoes it was 55 deg F night temps and 75 - 85 Deg F for daytime temps.

That's interesting -- basically that's summer here. This "summer" it's been in the 70s during the daytime and in the 50s at night, and I've had lots of large tomatoes for the first time. Usually, I rely on cherry tomatoes and saladettes for production, or just get fruit half the size it should be. (The typical summer has heat waves about once every month or two, starting in Feb. This year we had one 2-day heat wave where it got up to 103, then it was back in the 70s.)

As far as what they can tolerate and still produce, it depends on the variety. I get some production every year until the first frost, which has been the first week of December. They usually produce well during Sept., fall off in Oct., pretty much stop by mid-Oct., and eke out the occasional cherry (and, if I'm lucky, a random Stupice or Druzba) through Nov. The rains begin around Sept. Hoping for weather miracles, and because it's my last few tomatoes until May or June, I keep some plants going until they're blackened by frost. So I guess they can "survive" as long as temperatures don't hit freezing. It gets into the 40s at night in the fall, in fact it was 49F last night.

The microclimate makes a big difference as well. My garden site gets cool afternoon breezes all summer, and I don't have any thermal mass (such as stone walls) to collect daytime heat and release it at night. So when the temperature dips low enough, all the tender plants freeze. Row cover alone doesn't help. But at local gardens where the tomatoes are planted near a wall or under the eaves, it stays warm enough that the plants can survive and produce longer.