Cherry tomato vines can reach 12-15 feet. Not sure what you were thinking. Gosh, I guess you could wind them around the supports, and when you get to the top just allow them to drape down the sides. As long as you didn't over-indulge them in nitrogen fertilizer, you should get plenty of fruiting. I don't see any serious flowering until the vines get at least to six feet.

Thanks. Yes I've never had such successful tomatoes so far and wasn't expecting this. I could maybe rig something to keep them going up but will definitely need a ladder to get up there! If I top them off will it encourage more lower growth?

I have only fertilized twice so far with tomato tone which is low nitrogen. Fingers crossed for a good crop this summer - if I can get them before the squirrels.

Are you pruning? Single-stemming? I imagine that might help in crowded conditions. If worse comes to worse, you can always thin your plants. By thinning, I mean to remove some plants to make room for others. I recommend cutting any you remove down to the ground; don't pull them up, or you may disturb the other plants.

FYI rebar is a much better, long lasting, and stronger support. I literally had a cherry tom plant bend rebar. I think your current system will collapse in a month - I strongly suggest rebar. Try several around the outside then run string between at max height you want to grow to. String tomato plants along string at that height. They will easily go over 10 feet if allowed to.

Thanks - this is concerning - I have never had this problem before and didn't realize how big/heavy these plants can get. I have been pruning suckers - although I let 2-3 grow on each plant. I have all these cages zip-tied to each other so it does seem pretty solid - it's more like one big structure and they all support each other - but yeah, I suppose if each plant is adding several pounds of weight, I could see it starting to bend potentially.

I was thinking of putting 4 poles of some sort in the garden bed, one in each corner, and then running string across. Then what do I do? Have another string go from the top to the soil and then tie each plant to it as if it were a stake?

Would 2x2 wood poles work for this? I think I already have some extra pieces around. I also saw a solution someone had using PVC piping. If I were to do this over again, I probably would have gone with that method from the beginning - something like this https://www.feldoncentral.com/garden/tom_pvc/index.php?ind=2. 

That's a lotta tomato plants in a small area. You might want to keep them pruned up to help ensure air flow between the plants. Too much leaf in the middle can block air, causing mildew/fungal issues- and also too much shade in the plant cluster can really slow down fruit ripening.

The zip tied together cages like that can work- with smaller determinate tomato plants. But will hit the fail point with those big indeterminates, especially once they get laden with fruit. And if you ever get strong winds, forget it.

Use the 2x2 poles- sink into corners and also an additional set between the corners. If you can sink all the way down to the base of the bed, great. Then take heavy duty twine or wire, and weave a cage around your plants. As high up as you are willing to go. If you aren't good at making a weave secure, use small nails or upholstery tacks to wind around. If you got enough wood to place horozontal posts on the top to make the cage a square frame, so much the better- those top horozontals can be good support to drape the vines over when they get tall enough to drape.

Next year, don't use those tomato cages at all. But keep them for your peppers if you grow those, tomato cages are good for peppers. Plan in your supports next year for longer vines. Look into drop and shift. string trellis, low and lean. Those can help you work the big plants in the smaller area more effectively.

Yep that present set-up may present a problem once the plants get top heavy and a big storm hits town. I had to switch to 1/2" thick rebar to stake up my regular tomato plants as 3/8" would bend over later in the season once they got top heavy.

Would topping the plants be another solution? What is going to result in the most yield and still be manageable size-wise? Letting them continue to grow up, or topping them off?

I think it might be better to remove half the plants than to top off. I think your plants are too close together, so they are competing for nutrients and sun, which cuts back on your yield. They need good air circulation to protect against disease. I have 8 beefsteak type tomatoes in a raised bed that is 20 feet by 3 feet, planted 30 inches apart. They’re in Texas tomato cages that are 5 feet high. They will typically grow over the tops of the cages and hang down another 3 feet of more. By the end of the season, my garden can be a jungle. I used to grow more tomato plants because I wanted better yield, but learned that I get more if I give each plant more space. Topping off never worked well for me.

You'll get much better production if you give the plants more room to get some sun and air circulation. I think you'd get more tomatoes if you cut out some of the plants You might consider coming up with a support that angles away from the raised bed. That will save your plants for this year. Looking at your photo it looks like there's enough room for the plants to come towards the camera position??

I thought the rule of thumb for spacing tomatoes was 18"-24"...?

I'm going to cut two of the plants out. For the rest, can't decide if I should keep trying to rig something to let it go up or maybe I just let them come back down and hang over the side. Seems like people do both. If I remove some of the plants there should be more room to come down the sides too.

@carolb_w_fl_coastal_9b Although some people say that, it really depends on how you're growing them and what your goals are. Any time a spacing like that is recommended, it's a good idea to look at the conditions under which the spacing is used by those who advocate it. I mean, look at things like their light-levels, spacing between rows (not just between plants in a single row), cage height (or whether cages are used at all; cages aren't required in all climates; taller cages cast a longer shadow), the size of the plants used (and whether they're indeterminate, determinate, dwarfs, or micros), how much production they expect from each plant (some people who grow for flavor don't really care all that much if production isn't high), the direction of the rows (rows in different directions get different kinds/amounts of sun), soil constraints, etc.

So, I cut out two of my plants - one that was in the center which was getting crowded out (it was a Better Boy variety) and then took one away from the front corner as well (husky cherry red). Getting rid of the one in the middle was really key I think. Everything seems more airy now. I also took the extra cages and rigged them on top of the existing ones - so now I have some cages with 3 levels. I also put some stakes in the front of the bed and started anchoring them to the cages for more support. I'm going to let these grow to the tops of the cages again and then hopefully train them to go down the sides. If it starts feeling like it's leaning or needs more support, I plan to drive the 2x2s on the outside of the bed, and start anchoring the cages and/or plants to those. If the fruits get so heavy that the cages start bending, I'm sort of screwed I guess. Will be a learning experience for next year. I think next year I will do 4 plants, and do the PVC cages.

I had to stop growing sungold cherry tomatoes when I retired because I had nowhere to take a gallon of tomatoes each day!

Even now, with 3 plants for the 2 of us, I make plenty of sauce for the year, give some away to the neighbors and freeze some for other uses during the year!

FWIW, I use salvaged pieces of rebar, attached with wire, to anchor some cages and trellises.

And yes of course size/type of plants makes a difference in spacing. I grow indeterminates mostly, and plants need space for air circulation and ease of cultivation/harvest.

These are the tomato ladders I use:

And I use metal spiral stakes like these: