try the container grow ing forum or just look around

Lots of info already posted.

Here is a link that might be useful: Container search in tomato forum

5 gal is most definitely not going to be enough if you're growing anything besides a small determinate variety. I would HIGHLY suggest moving up to 15 gallon containers. My experience (along with numerous other peoples') was that the plants are miserably root bound in such containers. If you're staying under 3 or four feet, you should be fine. Otherwise, upgrade!

Here in Florida nematodes in the soil are problematic. I've been growing my maters in 5 gallons or less of Al's mix for years...these pictures are with 5 gallon nursery containers, which are actually 4 gallons of soil mix. I've been experimenting with with 3.5 and 5 gallon buckets this past year but weather was so bad that the jury is still out on the benefits of the buckets vs. traditional black nursery containers.

Tom

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Here is a link that might be useful: More background info....

Yes you can! I've been growing in containers that range from 5-10 gal for the last 4 years. Reason, my property sits on sandstone with only about 1 foot of topsoil. You can grow any type of tomato in a 5 gal. container whether it be determinate or indeterminate.
Aggregate I use peat, bark fines and perlite at a 3-1-1 ratio.I attach cages to my containers and secure them to a 60 foot long fence so they don't fall over from the wind or topple over due to fruit load.
You will have to supplement the plants with nutrients during the course of the growing season due to plant uptake and leaching due to constant watering. I use BioBizz Bio-Grow for my ferts. If you do live in the south you will have to water twice a day during hot spells and once a day or less during cooler periods or rain. An automated watering system would be advisable if growing several plants.
Make sure your containers are white in color to reflect the sunlight preventing the aggregate from heating up or the system tomncath use's burying the containers in mulch in a raised bed is an excellent idea when using dark containers or you can cover them with sheet styrofoam.
Yes it is a little more labor intensive but the results are well worth it. I'm growing 35 plants in containers this season in my back yard and 6 in a raised bed at work in my surrogate garden. Ami

Probably a good time to cover indeterminates that do well in smaller containers. My favs are; Beefmaster, Big Beef, Jetsetter and Brandy Boy, all the cherries and grapes do well in smaller containers, including the larger cherries like Sweet Chelsea.

Tom

Ofcourse you can-Our pots were probably 5 gal or less. The tomatoes were happy. Took seedling starts down to Fl. in yogurt containers, planted in pots for the winter and grew them on our porch. great experience!