Q:

What variety of tomato grows no taller than about 10 cm?

I saw a very small tomato plant (I think less than 10cm) in a tiny pot, and it was producing tomatoes. What varieties of tomato grow like this? 

A:

Seeing as you mean something like this:

Micro Tom Tomato

You really have two options:

Buy a plant (or plants).

Maybe you can buy "starts", I honestly don't know.

Buy some seeds and grow you own eg

Micro-Tom #6536 (30 seeds) $3.50 -- no affiliation, just a random site found via a web search.

Either way, there should be "growing", "plant requirement", etc information that comes with your purchase, regardless which option you decide to go with...

Good luck! and please post back a photo or two if you do grow a miniature tomato plant...

