Roma is a determinate variety and tops off at about 3-4 feet tall.

https://www.gardenweb.com/discussions/2766765/what-is-the-difference-between-determinate-and-indeterminate-tomatoes

The smaller size of your plant is due to the growing conditions, either the weather or the soil.

Rodney

How often have you fertilized it? You may need a blossom booster fertilizer.

Have fertilized every couple of weeks. Sprayed with a blossom set spray about a week ago. It is getting the same care as the other tomato plants in the garden. There are 8 other plants of varied types. Some are determinate some are not. This is the only one that isn't growing. I'm puzzled.

As mentioned a Roma plant will stop growing when it sets fruit (all at once).

IMO "blossom set" is something a garden center will sell you (to make money, of course) instead of telling you the reasons that fruit is not forming - and the reasons can simply be not enuff direct sunlight >6hrs, high temperatures, etc. or other things that "blossom set" can't/won't help with.

Blossom boosters are worthless. The plant needs to absorb that phosphorus in the 1st quarter of its life. It can get it from existing supplies in the soil or from general fert.