Welcome to the forum. I spent many years in Richmond and know Mechanicsville well. You've got a good sized garden there. If the garden is all you plan, I'd think a subcompact tractor would do well... Something like a John Deere 1025. The other major tractor brands are also pretty solid. I'd ask around about the best dealer and give them a preference. For a new machine owner, a good dealer is very important for support and advice. Make sure the tractor you pick is also comfortable to operate. There are big differences in how controls work. The only way to know what is right for you is to actually operate the machine around the dealer's lot.
Assuming you want to keep costs low, you may check around for used, but don't expect much. Pickins' were very slim around Richmond when I was there. People keep tractors a long time. But you can find used attachments. Watch the RTD and spread the word among area dealers about what you need. Use the Internet to get ball-park pricing - but you pay a little more for attachments "on the ground." You didn't mention it, but I'd sure go with a front end loader as well. It sure saves your back in hauling stuff, moving dirt and a million other things. I'll never again have a tractor without a FEL.