Howdy, Sheila!

You have options.

The trellis method gives a "skinny" plant because you prune off the bushiness. Packing plants closer together gives you more total yield per square foot.

The cage method gives a great bushy plant that may do better in some parts of the country. (Cages are mostly made of cement reinforcement wire, and are heavy. Staked with a T-post or 2, they hold up under pretty harsh wind conditions. You can cover with plastic for a mini-hothouse in spring, and top with shade cloth if your summer gets brutal. I think these cages usually take up 2x2 squares.

WARNING: Standard (~3-ft) funnel-shaped "tomato cages" from the store are hilarious as tomatoe supports. They do pretty good jobs with eggplants and peppers, though.

A variation is to make a wider cage, fill it with aged compost, and plant around the outside of the cage. Water down into the compost to continually feed the plants through the season.

Here is a link to a Master Gardener evaluation of lots of options to control tomatoes with stake, trellis or cage choices. They include recommended plant types, pruning required for each method, advantages, disadvantages and how-to-build. Photos look helpful.

Here is a link that might be useful: Tomato Stake, Trellis, and Cage Reviews and Building Guides

Jacque,

Thank you so much for the advice. The link you left is very informative.

I have always used the cheap "tomato cages" in the past and every year my tomatoes end up all over the place because the cage isn't large enough or strong enough. Trying new things is sometimes hard, but I'm looking forward to having happier more upright tomato plants.

I'm very excited about starting my first square foot garden. I've been going over my planting plans every night. Today I went to Lowe's and priced some of the items I will need. It's still cold here in Virginia, but I will be setting up my frames soon.