IMHO, it's a personal preference thing. I don't like pruning, but my wife does. We have a very hot dry summer climate and I feel the extra foliage helps protect the fruit and create better micro climates for fruit. On the flip, My wife feels the plant uses more energy to create foliage that could be focused into fruiting.

We've struck a happy medium of selective pruning - keep plants to a single leader, and prune off all branches on the bottom that hang to the ground with or without fruit. Also, removal of any dead, diseased, or pest attacked limbs pruning out as far as can be done on the branch to limit stress.

I think it has a lot to do with your specific situation and your grow style. I don't think there is a right or wrong way.

Limiting the suckers and topping off the plant can tell it to concentrate on the current fruits already on the plants. Especially useful if you have a short season before frost. Or is if you're growing in a container and have a small cage and trellis.

The main reasons for me are:
-The plant gets to big and tall for me to handle, I'm no longer fond of carrying ladders around to manage my tomatoes.

-To create airflow through the plant, especially the bottom area, which help with reducing pests and diseases. (whiteflies loves the bottom leaves of the plant). I have saved some of larger my plants before by removing all diseased leaves before they can spread, though this depends on the type of disease.

I'm skeptical of the idea of reducing leaves because 'it takes energy away' from the fruits, I'm not a scientist so I can't say, but it doesn't make sense. Of course, the fruits may take longer to mature, but the leaves are there to make glucose and probably contribute to the final flavor of the fruit, not just the roots (?). I would assume that the nutrients between the leaves and the fruits in the plants are not isolated. I'm betting that if you grow watermelon and cut off 95% of the foliage and leave only the naked vine and fruits, the fruits probably won't be as flavorful. Perhaps it's more of the effect of allowing more suckers thus more leaves, but also more blossoms and therefore more fruits, then the flavors are more diluted. Perhaps it's more a problem if you grow in containers or poor soil where the nutrients run out. But my Black Cherry that I grow in soil continues to taste sweet even to the end of the plant life when it was almost 20ft. Someone who knows more about the science can prove me wrong.

WSU extension is where the pruning for energy focus idea comes from.

"In short-season locations, pruning will
allow the plant to
focus energy on fruit production. If left on the plant, suckers unnecessarily
divert water and energy that would otherwise be used for
fruit development"

http://extension.wsu.edu/snohomish/wp-content/uploads/sites/7/2014/08/Growing-Tomatoes.pdf

Well that guide confirmed my point, "Pruning indeterminate
plants will
not increase overall
tomato production
but will give you
larger fruit earlier in
the season. ".

What I like to know and concerned with is whether you are limiting the suckers and amount of blossoms, or are you pruning the leaves as well, and whether it's counterproductive toward developing the flavor and nutrients in the fruit if you were to remove a large portion of the leaves from the plants, which many growers seems to do. I'm also concerned about how pruning affect new blossoms production.

Also they said "To determine how long it takes for an overhead sprinkler" and "overhead sprinkler". (Overhead) sprinkler + tomato plants = bad news.

"wondering how the decision to prune or not prune is affected by climate. I live in SC, zone 7b, right on the border of 8a. Our summers are hot and humid, and I wonder if leaving a tomato plant to grow unpruned and thus with crowded leaves and branches and thicker growth would inhibit evaporation and cause more shading that could lead to problems with disease."

As a southern grower in a hot and humid climate on about your same latitude I have discovered over the years that it is your plant spacing that eliminates those problems, not the pruning or non-pruning.

If you insist on over-crowding the plants as some do due to limited available space vs. large number of plants then yes, you will have to prune aggressively. If, on the other hand you have the room to space your plants widely (1 sq. foot min. 4 sq;' better) then you won't.

It also makes big difference in how you plan to support your plants - Florida weave, cages or stakes, and how tall and wide your support structure.

So can you provide details on the varieties you will be growing, how you plan to support them, and how much room you'll have available for how many plants?

Dave

Thanks for the comments. I am most concerned with the issue of disease rather than production, but thanks for the link. Interesting reading!

maxjohnson- what has been your experience with disease in Florida?

digdirt- I would love to hear more about your experiences with disease in your tomato garden. It does sound like we have similar climate.

Since we are trying to start small so as not to overwhelm ourselves, Tomatoes will be relegated to a 4x10 raised bed, 12" deep (with 3 others for other vegetables). Not a lot of room, I know, and i was hoping to squeeze some peppers in along the edge!

Varieties? So far I have Pruden's Purple, which I read can do well in the heat and humidity. I would also love to try Indian Stripe and figure I should include a hybrid or two. SunGold? Brandy Boy? Big Beef? Opalka sounds great for making sauce...Decisions, decisions.

I have no definite plans regarding support yet. I was figuring that pruning might be the way to go in my situation, so had ruled out cages. I like the look of fence trellises, and dislike the look of Florida weave. There's lots of bamboo around here, so stakes are a possibility as well.

There are all kind of diseases in Florida, certain plants don't grow as well in high humidity which also promote more of diseases and pests. There are root knot nematodes in the soil so many people only grow in containers with fresh potting mix. Also lots of rain. Arguably it's the worst state to grow tomatoes.

My opinion is to grow what you like and see how it does, and continue with the variety works for you. The ones you mentioned are already very good choice. Cherokee Purple does really well and is early for me down here, so Indian Stripe probably will be good.

For spacing, it really depends on how many stem you will allow the plant to have. If you grow an indetermined beefsteak and not prune, I would give it at least 2ft on both side, but 3ft is better.

Cattle fencing is a good choice if you can get them.

Yes, I'm really excited about trying indian stripe! So do you prune your tomatoes? How have they fared with regard to foliar disease?

It sounds crazy, but I prune more for the whiteflies which is a problem around here because they carry tomato yellow leaf curl virus (TYLCV), which is a death sentence for tomato plants. I fear it more than regular diseases. Whiteflies prefer warmer weather, unfortunately it has been unnaturally warm this 'winter'.

I think sometimes it comes down to luck and can't be controlled because there are many airborne diseases, even if you grow in clean potting mix, they are more pervasive during rainy season and the leaves stay wet.

It has been fairly dry for Florida this year so it has been very good growing. They say a good year for tomato growing is a drought year.

People do spray copper or daconil as fungal prevention, but I don't do that. You can buy certain hybrid variety that resists certain diseases.

-interesting about the whiteflies. It feels strange to me to go into this having no idea of what kind of disease or insect problems to expect.

It's better to not get overly worried about small details when you're just starting out. It's probably more fun to figure it out as you go. If you are stressed about it then it's not worth doing as a hobby. Sometimes you'll get great harvest by not doing anything. It is possible to 'doctor' the plants too much and does more harm. If you tries to take in too much info before even doing it, you'll get confused and it becomes a clinical experience where you're expecting certain results instead of enjoying it.

In short this is what I do (which is not the same as others):
-prune suckers to allow some airflow
-remove bottom sick or yellowing leaves
-spray with cold pressed neem oil + peppermint soap to prevent pests
-mulch
-pray it doesn't rain

leave pruning to greenhouses.. let nature run its course.. no need to baby sit them.. the more you fuss with them the greater the chance for problems. :)
the only area i would suggest pruning is the foliage close to the ground.. ie around 8-10 inches.. you don't want any part of the tomato plant touching the ground, except the main stem of course. if you hand water avoid splashing soil onto the plant.. mulch solves most of these problems.

"Tomatoes will be relegated to a 4x10 raised bed, 12" deep (with 3 others for other vegetables). Not a lot of room, I know, and i was hoping to squeeze some peppers in along the edge!"

In that case you'd only have room for 3 unpruned tomato plants of the varieties you mentioned. If you prune them to a single stem and use stakes you could squeeze in 5 plants. Any more than that and disease and pest problems would be a real concern.

And if you opt for stakes then single or double stem pruning is almost mandatory. It will cost you production.

As for pests disease in my garden - Hornworms and stink bugs are my primary pest issues. Septoria and Early Blight are as much of a problem for me as for any other tomato grower - they are universal - as the airborne fungus thrives in heat and humidity. In fact they are one of the reasons that I increase my spacing so much and do not prune. That way as foliage gets infected I can remove it as needed and still have lots of healthy foliage with sufficient fruit protection. If I pruned aggressively from day one by the time the disease processes kick in there would be very little foliage left to remove - bare stems and sun burned fruit.

Dave

PS: As for the claim ""Pruning indeterminate plants will not increase overall tomato production but will give you larger fruit earlier in the season. " A grain of salt. Other studies show that not only is overall production reduced markedly but increase in fruit size, if any, is minimal.

There is different versions of pruning:

1- pruning leaf branches (especially lower one) to provide better air circulation (under and within the plant) and minimize fungal diseases.If you get a lot of rain and high humidity this can be beneficial.

2- pruning side branches (suckers ?) to keep the plant size in check. This is necessary if you plant them closely ( as Dave mentioned ), less than 2 ft spacing ( 4 sq-ft per plant).

3_ pruning due to support system : If you support your tomatoes by stringing/layering you have to prune to a single stem. I am going to try one row that way. In this method you can plan them closely as they won't get bushy at all, Just a single stem.

Now that I am in new location with ample space, I will give my plant more space., maybe 30 inches. So I will keep more side branches, and do less pruning that I used to do in the past.

Sey

Interesting. Let's just say I don't have a formal tomato-growing support system... big tomato plants like Sun Gold and Brandywine tend to take over, flop over, and grow so long that they eat parts of my yard. lol! Is it really ok to cut back all the long stems to try to keep the plants in check??? It never occurred to me to try it! I guess I figured that cutting the stems/tips would be likely to shock the plant, lose fruit production, and even open the plant up for contracting disease.

TY! And, yeah, but that's how I live my life. lol!

From my experience, growing in soil, my Black Cherry gets up to 20ft at the end of the season (bending over toward the ground and grows back up) and it still produces well. I guess topping off the plant may help with larger fruits (digdirt2 above said it probably doesn't). For me it's more about limiting the amount of suckers and how crowded the plant gets, to get airflow for pests and diseases prevention, not so much how it affect productions. I personally feel the leaves are more susceptible to getting infections when it's very crowded eventually (which is usually my fault for crowding the plants in the first place).

"3_ pruning due to support system : If you support your tomatoes by stringing/layering you have to prune to a single stem. I am going to try one row that way. In this method you can plan them closely as they won't get bushy at all, Just a single stem."

Not necessarily... I prune each plant to three stems and I train them to twine up suspended string. I can plant close to 35% more plants using this method.

In stringing/layering the tip of stem is kept at about 6 ft. As the plant grows taller you let it to come down (AS YOU PRUNE THE LOWER LEAF BRANCHES) and the naked stem rests on the ground. With more than one stem it cannot be done because each stem will grow at different rate.

This is how commercial greenhouse growers do it.

Sey

Sunscald is a real problem for me, and seems worse on Big Beefs. The larger the canopy, the less sun scald resistant the tomatoes seem to be. They grow a big canopy for a reason. The canopy also helps hide the treasure from the birds.

I don't recall ever seeing a sunburnt Sun Gold. The canopy on sun golds I have grown is thinner.

I don't prune. I mulch the soil under the plant for two reasons: to minimize splashing (backsplash from a hard rain) upon the leaves and any leaf disease transfers that might happen from the splash' and to keep the ground cool and hold moisture longer.

I do remove the lowest leaves as they start to fade.

In my 9a zone here, getting a plant to survive through the hot summer months is a bigger challenge than leaf diseases. A plant with intact leaves doesn't function right here after the trip through summer. A potted plant might provide some shading/cooling options. I am still planting in the ground, no root knot nematodes yet.

Thanks so much, everyone, for the information and for sharing your experiences. After thinking about it more, though I would like to experiment with not pruning at some point, I would really like to grow more than three plants my first year, if only so that I can sample more varieties. :)

If I were to plan 4 square feet per plant, could I prune to three or four stems? Im leaning toward using a fence for support.

With four sq-ft per plant, You can prune to 3 to 4 stems. But need to support them with more than one stake. But things can start looking like a jungle.

You can get an idea how I support mine, which I prune to three stems per plant.