Many people, even those of us in the snow country, grow or have grown tomatoes all winter. Low light conditions for many of us makes it a bit difficult but not impossible.

Here is a link that might be useful: Tomato growing in winter

I would like to welcome anyone that has tried to grow tomatoes organically through Winter to discuss their experiences.

In Z10 (Phoenix AZ, SoCal, etc ... it's easy to grow tomatoes year round as long as it doesn't freeze.

They ripen slowly, but as long as the pollinators are active, it works. I'm not doing it now for lack of time.

These were "Ruby Pusa" tomatoes from India, growing in a compost bin under a mesquite. Slightly sheltered, picked when they first started to ripen, and brought inside.

Here is a link that might be useful: Tomatoes in January

How is the sweet vs acid quality...specifically the sweetness...on the Dec+ ripening toms vs in-season ripening toms?

Here in NC you can grow them under glass, but you need to bring supplemental lighting as well as additional climate heat in order to keep the sweet/acid balance from tipping too far to acid.

Variety type helps, but no variety type can take care of the sweet/acid balance issue on it's own.

nc-crn, taste is very subjective. These are 'Early Girl', which perform very well in my locale. Would you expect the flavor to be different in the Winter? Personally, I can't tell any difference.

I don't know how to gauge them in SoCal being that I'm 3000 miles and a few climate ticks away.

Even a couple states South of me in Georgia, winter tomatoes grown under glass aren't as sweet as the same varieties grown in ideal summer conditions without supplemental help.

Regional differences of harvested crops on the margins of seasons (both early and late) is an interest of mine.

If you are trying to compare a tomato purchased in a store, which is picked long before it has begun to develop the sugars and such that make the tomato taste, to one grown in a home garden and picked at the proper time you are wasting your time. All the fruits and vegetables sold in a grocers today are picked way too early to allow for sorting, packing, and shipping to reach the grocers shelves before they start to rot. The only place, other than your garden, to get fruits and vegetables that have developed their flavors is at your local farmers market when those fruits and vegetables are in season on your area.

I'm not trying to do that. I'm well aware of those issues.

I'm trying to gauge the effect of less quality daylight and lower temperature on the flavor (sweet vs acid) of tomatoes in various parts of the world by sourcing out the question to people growing them...and presumably have grown the same variety during more favorable times of year.

Some people notice little difference in the sweet/acid balance...for some it's quite drastic in flavor.

It's informal, but I've been doing it for years. I have a semi-weird interest in garden behavior in varying climates.

@kimmsr, do you garden in the winter organically?

It should be noted that there are a number of excellent mass produced tomatoes that are readily available at the grocery store. Kumato and Campari come quickly to mind.

@nc-crn, sounds like an interesting endeavor. For me, tomatoes are an important ingredient in so many dishes that I just try to have them around all the time. I don't can or process anything, everything I grow is for fresh eating/cooking. My palate may not be developed well enough to note subtle differences in tomatoes. It's one of those "I know what I like when I taste it" sort of things. If a tomato is tasty, produces well, is disease and pest resistant, it's a winner for me.

The winter tomatoes were less flavorful than the ones from earlier in the season. Also, the cooler temperatures affected the texture - they had the "grainy" texture you see in tomatoes stored in a refrigerator.

Being picked mostly green and ripened inside probably didn't help.

To be honest, the Mexican field-grown Romas from Food City were better.

It was an experiment, and I was growing them mostly to get more seeds for some Indian friends. It's an Indian heirloom variety and they only had a few seeds to work with. During the summer and fall I was vine ripening them and saving seeds. It's a very juicy, tart variety and makes excellent curries and Indian sauces. Definitely not a slicer or salad tomato.

lazygardens, I have seen a number of "mealy" Winter grown tomatoes in the past. There hasn't been a single one from the EarthBoxes yet this season. This leads me to believe that the mealiness may be tied to water availability/uptake and not just cold over night temps.

"To be honest, the Mexican field-grown Romas from Food City were better."

Being from the East Coast...and a lover of Arizona (especially Tucson)...I am super jealous of both Food City and Sprouts.

We have Whole Foods here...and their idea of having a sale is letting you buy something slightly overpriced rather than greatly overpriced. Sprouts puts it to shame...and Food City always has avocados, tomatoes, potatoes, etc for give-away prices no matter the season.

Here we go again:

here at latitude 41deg the tomatoes become poorly flavored in October due to low light and cool temps. Winter-grown plants is impossible without both a glasshouse and artificial heat. They do it down the road from me and claim it is a net gain but without cheap electricity they would not do it.

I would think winter grown tomatoes are only feasible from about 30deg southward.

I have grown winter tomatoes in a greenhouse in New Mexico for years, and find that some of the older, less acid tomatoes retain their flavor better than most of the newer hybrids. Yellow pear, in particular, is an amazing producer of very flavorful tomatoes throughout the winter. Mortgage buster (or some similar name) is another, larger good tomato. Neither of these suffer from BEA, and tend to keep flowering as the days get shorter. If you want to spend the money, some of the tomatoes intended specifically for greenhouse growing such as Arbason and Cobra, produce like crazy, and can be kept growing for many more months into the summer.
Renais

For Winter growing it's important to have a variety that will flavor up nicely if harvested at breaker stage for ripening on the kitchen counter. I rarely allow Winter tomatoes to fully ripen on the vine. It takes too long and there can be flavor loss --like when you store a tomato in a refrigerator. After many years of trials, 'Early Girl' does best in my locale. 'Stupice' comes in second because it appears to be less cold tolerant.

Have some Johnson German heirloom tomatoes in a bed on the southside of house and 2 in containers on the sun porch. We can get freezes here in NC Florida, so don't know if we can keep the outside ones going, but the porch ones should be ok. Have them on the sunnyside of the porch. We were fighting heat just a few days ago, now it's perfect after a cold snap.

Here is a link that might be useful: Winter Tomatoes

Starting to set fruit. No BER or foliage problems so far:

So I am giving it a go this year too. I have a couple of tomato plants growing in my greenhouse. What is the lowest allowable temp? Also do extreme temp swings damage the fruit? It can get pretty warm in the daytime in there. Thanks.

I have very good luck in the winter greenhouse letting the daytime temperatures climb into the high 90s so that I can heat my passive solar storage, and letting the night time temperatures go down to about 45. There are sunny days when the temperature goes over 100 with no noticable deliterious effects. I water automatically twice a day on a drip system, and grow in mostly 2 or 3 gallon containers. The plants become huge over time because I don't bother pruning suckers or laterals. Plants are spaced about 3' apart in a row, and trellised so that they grow up about 10', and then hang down again. The plants look quite messy and unkempt, but they produce lots of good fruit. Here are some of the current varieties I'm growing. Arbason is a mid-sized tomato with very vigorous growth. It, like almost all the varieties I grow, is resistant to blossom end rot. There are a few heirlooms that get BER even with the regular doses of calcium nitrate I use in the fertilizer. Fruit is still good tasting, just ugly. Verona is a small tomato, larger than a cherry, with good production as a salad addition. Sun Gold is a yellow cherry that visitors often really like. It has a low acid taste, and is quite productive. Yellow pear is probably the favorite tomato of visitors; it produces huge numbers of low acid fruits on a vine that sprawls all over the place. One plant is well over 8' wide, and trellised at several points. This is a tomato that even those who say they don't like tomatoes like. I grow Brandywine, and find the flavor ok in the winter greenhouse, but it can get to be a bit meally, and I don't think it is as tasty in texture as some of the others mentioned. It is a quite large fruit, however. Other heirlooms also tend to get a bit meally during the winter, and I am slowly moving toward growing more of the modern varieties specifically bred for greenhouse production because of the better textures and flavors in the winter.
Renais

Excellent feedback Renais. Thank you.

I cover my Winter tomatoes if the overnight forecast calls for under 40 degree weather. The hard scape tends to hold the heat OK, as does the water in the EarthBoxes. All bets are off under 32 degrees.