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applestar
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Cool Temp range that affects tomato fruit maturing/ripening?

Here in NJ, tomatoes start to set fruit around late may to mid June and the green fruits mature and ripen by early July if you try really hard or more like mid-late July until frost. Unless there is a serious heat wave (like we did this past season) there is usually no interruption in fruit harvest although there are plenty of green fruits at frost.

So I'm realizing I've never really took notice of what kind colder temp range affects tomato fruiting and maturing to ripe fruit. especially in the first fruiting stages.

Right now, [url=https://helpfulgardener.com/forum/viewtopic.php?t=48807]my winter indoor tomatoes[/url] are all starting to bloom and set fruit.
The temps downstairs fall to upper 50's at night and typically reach upper 60's during the day. Temps upstairs fall to mid-60's at night and typically reach low70's.

So the temps don't seem to be affecting fruit set, but by my summer temperature standards (mid-upper 80's/upper 60's-low 70's) these temps seem way too low for seeing ripe fruits. What are the minimum temps you really want when the tomato plants are in fruit production stage?

This is precisely the reason for trying Sophie's Choice which is supposed to be coool weather tolerant/hot weather intolerant. So please discuss the cooler weather tomatoes varieties as well the average varieties. I think I need to discover and differentiate heat-loving varieties to weed out of the winter indoor grow list as well. Late maturing (long DTM) varieties are definitely out, extra early and early are definitely in.

If you are familiar with any of them, from what I'm growing -- besides Sophie's Choice -- Zarnitsa, Donomater, and Black Krim, which are more cool weather fruit maturing varieties? Maybe the evaluation can be expressed in terms of how well they do in heat (assuming they don't do as well when cold).

What are the varieties you all are growing in cool summer areas and what is the average/typical daytime highs/overnight lows when the tomatoes are fruiting and ripening?
Last edited by applestar on Sat Dec 01, 2012 12:23 pm, edited 1 time in total.

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digitS'
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Variety is important, Applestar.

First of all, I don't have any experience with the varieties that you are growing. We read some about those like Sophie's Choice that are supposed to set fruit in cooler temperatures. I have grown Stupice, Legend, Bloody Butcher, Kimberley . . . maybe 1 or 2 others which have this claim made about them. I believe that it has been shown to be true in my garden.

I looked back on 2 years, 2010 & 2012 -- they had 14 & 16 June nights with temperatures above 50°F. Nights didn't consistently stay above 50° until the 6th & 7th of July. The golden cherries (Sungold & SunSugar) will begin ripening their 1st fruits about that time. Something like a Bloody Butcher or Kimberley will show up about mid-July. Plants with beefsteak-size fruit won't have any ripe until well into August.

Honestly, the very early plants may be setting fruit in the greenhouse before going out into the garden - they are all out there in late May. Until then, they were still in the greenhouse with overnight temps of 60°F. I do remove any small fruit that I see on the plants when they are set out.

If it takes about 50+ days for a plant to go from open flower to ripe fruit, that really seems to suggest that pollination took place prior to going into the open garden. However, the fruit that begins to show up in good numbers in mid-August must be from flowers that were pollinated in mid-June, well after the plants were out in the garden. The overnight temperatures were usually in the high 40's about then and certainly not over about 54° on any given night.

Okay, those are the early guys. I know I've said something about growing Dagma's Perfection and being completely caught off-guard by how it set fruit late but ripened quickly. The flowers probably could not be pollinated until the overnight temperatures were above about 55° every night. Then, it was off to the races.

I hardly know what to say about some others that will only ripen in mid-September, perhaps even after being picked and brought indoors. I have grown varieties that are rated as 80 days-to-maturity and had them ripen 1 fruit outdoors by the end of the season.

Steve
We are each other's harvest; we are each other's business; we are each other's magnitude and bond. ~ Gwendolyn Brooks

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digitS'
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I'll say that Rutgers has lots of tomato information! Here are varieties that shows up in a google search:

Season: "Very Early" (link)

Steve :)
We are each other's harvest; we are each other's business; we are each other's magnitude and bond. ~ Gwendolyn Brooks

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applestar
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Thanks, digitS. I was thinking you would be one of the forum members who would have experience with tomato growing in cooler season. :D

So far, I've been buzzing the blooms almost every day several times with electric toothbrush, and the temperature doesnt seem to be affecting pollination/fruit set. And your records showing that earliest cherries start ripening despite the 50's temp seems to be a good sign, though I suspect that their daytime high's IN DIRECT SUN would be a lot higher than the measly low 70's....

Btw, Donomaters have been flashing green immature flower trusses for a while now without actually blooming. I think they slowed down a bit. These may prefer warmer temps. In comparison, Sophie's Choice's were earliest to bloom and each have at least one 1-1/2" to 2"+ (biggest is about 2.5" and starting to get shiny) fruit as well as additional pea to marble sized fruits, but 2nd to bloom Zarnitsa's are more prolific and numerous in bloom -- currently sporting 4-6 pea to marble-sized green fruits on each plant. (These two were started from seed on Sept 2.) Black Krim's have first fruit sets -- still barely discernible.

If I start getting ripe fruits by the end of December to early January, I think this would satisfy the transition from just before frost, green harvested, ripened in cardboard boxes fruits to Winter indoor harvested fruit.:()

I did find this:
The optimum temperature range for ripening mature green tomatoes is 68–77 deg. F. The further temperatures stray from the optimum, the slower the ripening process will be. And, when temperatures are outside the optimum range for extended periods, conditions may become so stressful that the ripening process virtually halts.
https://www.hort.purdue.edu/ext/tomatoesnotripening.html

So I'm thinking I would like to move some more of the fruiting plants upstairs. I can make room by bringing 2 avocados downstairs, but to accomodate any more, I'll have to set up more lights. :roll:

I'd still like to hear more about other people's personal experiences with different, supposedly cool weather tolerant and extra to extra-early varieties though. Good performers and bad? What were your average daytime high's and overnight cold temps? Any dwarf/recommended for container growing varieties known to have these characteristics, or known to be particularly sensitive to heat (and by extrapolation, more tolerant of cooler temps)? Those would be the three top criteria for varieties suitable for "Winter Indoor" growing. :wink:

OT in my own thread :> -- For 2013 season main tomato garden, I'm going to plant larger sized beefsteaks that are described as maturing early to early-mid season and have great flavor. Some of them will be bi-colors and other non-reds. You may be interested in the results, digitS. 8)

Dillbert
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>>about other people's personal experiences

they bloomed, they set fruit, fruit never quite reached golf ball size.
never turned even pinkish.
whitefly heaven . . .

end of story.

I wasn't working with specific cold tolerant types - I rooted plants from garden cuttings to short cut the sprouting.

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prettygurl
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It is a good question. I have had a terrible time this year with the crazy weather. The temps are like a seesaw. I noticed two things. First, my garden shut down after the temps hit 86. The plants don't seem to like when the temps get to high. Second, they don't like drastic changes. Mine didn't like it when the temps dropped more than 15 degrees at night.

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digitS'
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So far, I've been buzzing the blooms almost every day several times with electric toothbrush, and the temperature doesnt seem to be affecting pollination/fruit set. And your records showing that earliest cherries start ripening despite the 50's temp seems to be a good sign, though I suspect that their daytime high's IN DIRECT SUN would be a lot higher than the measly low 70's....
The direct sunlight would make a difference but the air temperature wasn't a lot higher than the low 70's:

June, 2010

14 afternoon highs above 70°
3 of those above 80°

June, 2012

17 afternoon highs above 70°
3 of those above 80°

So you see, half the June days didn't even reach 70°F. I'm not saying that this is good . . . more like misfortune :roll: .

After July 4th, things begin to warm up. Afternoons consistently hit above 80° with a good deal of 90's later in the month. Then, those early variety tomatoes on the plants ripen! But, pollination & fruit set occurred during those cool days & nights earlier.

You may be wondering why I've skipped 2011 -- There was a record cool spring that year :roll: . Look! Things could be worse if I was living on the westside of the Cascades - temperatures cool and about the same most any day (& night) of the year with sometimes a zero chance of a ripe beefsteak. I've got 4 seasons here in the Inter-Mountain part of the country. (And, we are just getting to the stormy, snowy part of it!)

Keep that toothbrush handy, Applestar! And yes, you may want to get those plants with nice tomatoes up where it is warmer! That Sophie's Choice looks like it was a good idea!

Steve :)
We are each other's harvest; we are each other's business; we are each other's magnitude and bond. ~ Gwendolyn Brooks

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