Ann, at the top of this first page there is a link to the FAQ's and the very first article is about the difference between determinate and indeterminate varieties and those terms describe the plant habit of tomato varieties. Det ones are shirt and bushy and most tend not to produce all season while indet have long vines and tend to produce fruits all season. There are far more indet varieties than det ones.

It's helpful in terms of knowing how far apart to plant your plants and how to grow them either by sprawling or in cages or by staking or in containers, or however else you might want to grow your tomatoes.

As for the white cores, Google is your friend and below I've linked to a Google search for white cores and most of the time they appear when plants are stressed as you'll find out when you read some of the links.

And in Utah, as opposed to NC, your tomatoes are much more likely to be stressed. So read some of the links within the Google search I posted below and see how to hopefully get around the stresses.

Hope that helps.

Carolyn

Here is a link that might be useful: White Cores

Thank you very much for the information. I am sorry I did not do my homework first, that would have been the thing to do.
Ann

I think you will also find that your plant out date differs greatly where you are now from when you planted in NC. That alone can reduce much of the stress on your plants.

And as always when trying to garden in a new location, other local gardeners can be a wealth of info. If there is a local Farmer's Market that is a great place to meet them and don't hesitate to ask them questions. They love talking gardening with customers or even browsers.

Dave