This is the first year that I am growing all of my 14 tomato plants in smart pots. The fabric pots are 30 gallon pots filled with excellent potting mix (fox farm potting mix). I have always grown in raised beds for the past 18 years. Last year my plants got hit with Tomato Mosaic Virus (TMV) and my whole crop got decimated. TMV is very contagious, but it also stays in your soil for a long time. I wanted to continue to grow tomatoes and since I only have one place on my property that I can grow I had to devise a new solution. I dug out all the soil in the raised beds. Then I lined the beds with plastic, laid wooden struts along the bottom to create a raised platform, and placed the 30 gallon smart pots on top of the wooden struts. This way the pots can get better aeration and they wont sit in any standing water that leaches out the bottom of the pots. It also keeps the roots from reaching down into the potentially contaminated soil. I've been feeding every 2 weeks with Happy Frog Tomato and Veg fertilizer, and watering roughly every 3 days, checking the moisture levels to make sure its not too dry and not too wet.
I thought that 30 gallon smart pots would be sufficient to grow large healthy plants, but I'm surprised to find the the plants are significantly smaller as are the fruits. 2 years ago (before the TMV hit) my plant on this date were 2-3 feet higher than they are now and were loaded with much larger fruit. I'm getting good fruit set this year but the fruits are very small. A Brandy Boy, which should be a decent sized slicer (12-14 oz) is producing fruit that is ripening at 2-3 oz. Oaxacan Jewel which is supposed to be a larger slicer is also doing the same.
I am wondering if I'm not watering enough. I don't want to over water the tomato plants, but I'm suspicious that I might be underwatering. Currently they are getting watered approximately every 3 days. I water each plant using a hose end wand waterer at the base of the plant, for a count of about 8 seconds, which generates about a gallon of water per plant. Could it be that the water is not going deep enough into the smart pots? The plants look very healthy, just smaller with smaller fruit. This weekend I added some epsom salts to the soil along with a compost tea drench.
What are your thoughts about growing in large fabric pots vs. raised beds, and do you have any specific recommendations about watering techniques. I'm including 2 pics to compare the plants growing in the beds vs smart pots. These were planted on the same date and the pix were taken on the same date, just 2 years apart. (Note: We were getting the patio repaved in the first pic so the ground was lower and dirt. But they are the same location)
Thanks all

Temperature has a dramatic effect on fruit size.
Soil possibly too hot vs the raised bed temps.
I would monitor the soil temp with a digital thermometer just to see what it is.

That’s interesting! Here in Florida I’ve grown exclusively in fabric pots as the soil sucks. My garden in Massachusetts had fantastic soil, but my tomato plants are pretty much the same size FL vs. MA.
I’m using a homemade 5-1-1 soilless mix now instead of bagged potting soil. It’s worked out very well. I’ve done a bit of planting in a couple of the Foxfarm mixes for other veggies and remember them as very finely textured and water retentive. If you have a source for pine bark fines you can make a nice grow mix to supplement the Foxfarm next season.
Here’s the mix in progress. Pine bark fines, coarse perlite and coco coir, plus dry fertilizer, epsom salts, a bit of garden lime and a little azomite.

Back in the heatwave last year I had plants in containers.
The soil temp was 87 degrees f
The plants didn't last a month.

I have a batch of plants in 2 hole cement blocks,a plant in every other hole.
Stacked 3 high for people that can't bend easily.
I snaked an armored garden hose through the holes and pump warm rain water
to keep the soil warm.Once the heatwave hits I will pump cool water, 12v pump.
Originally I had an electric heat cable on a timer,but vermin ate the insulation off.
I hate when that happens.
Normally it is used for rain gutters to keep them free of ice in the winter.

Planjane, I can't quite read the whole name of the brand for your bark fines mulch. I just got a bag of soil conditioner which contains bark fines but am running out and the garden center where I got it is out of it. Besides straw bales, I use a Smart Pot type pot and Earthboxes. For the containers and EB's I have usually used Coir, perlite, granular fertilizer, Dolomitic Lime, some chicken/rabbit manure, bonemeal and worm castings. I also have some composted cow manure and mushroom compost I can add as well. The soil conditioner sounds like a great addition to my mix as well. The Earthboxes will be used for Eggplants and the pots for both. Can you supply me with the name of your bark fines and where I might find it? Thanks.

Thanks for all the recommendations on planting mixes. I'm wondering how much do you water in smart pots? I've been watering each 30 gallon pot with a little more than a gallon every 3 days. I'm thinking that may be too little which is why my plants and fruits are so small. I'm always concerned about over watering. But maybe with the smart pots you can't over water. My pots are raised off the ground on wooden struts so maybe extra water will just run out anyway.
What are your recommendations on watering in 30 gallon smart pots?