Pentex Number one thing is sun, the more they get, the more tomatoes you'll get.
I do many thing, when I plant I dig a huge hole 3 times the size of the root ball. I put 2 inches of compost in the bottom of the hole fill it with water. Remove all the side shoots, and try to plant the tomato as deep as I can 6 to 8 inches deep. I remove all the suckers for about a month to a month a half. After that I just let them go.
I feed with miracle-gro every other week.
Whether or not the fruit sets does depend on the weather and bees. This year has been a terrible start in Mass, not much sun, lots of rain and cold nights. Everything tomatoes hate.
I was very excited I had flowers on my plants in May, then the second set of flowers in early June. Neither set of flowers did much of anything. I have some tomatoes but nothing to brag about. My plants are now 3 feet tall, getting their 5 set of flowers, with a little luck this could be a good tomato year, late but good.