Can You Really Grow Tomatoes Upside Down?
Yes, tomatoes can be grown upside down!
Tomatoes can be grown just about anywhere there is enough sun, in very little space.
No need to support the tomato plant.
Plant is not near soil borne insects and diseases.
No need for weed control.
A mature tomato plant with fruit plus wet potting soil will get very heavy, choose your support carefully. In full sun, these relatively small containers can dry out rapidly and expose roots to high temperatures. The plant will try to right itself (towards light, away from gravity), but as it grows, the weight of the plant will keep it growing downward but the stem may also break.
Choose a determinate type tomato plant.
Use an adequately sized light-colored pot that won't get too warm during hot days. Plant the rootball as close to the top of the container as possible, so the roots have more room to fill the pot before hitting the bottom. The roots will continue to grow downward from the rootball until they hit the bottom of the pot and then grow in circles to fill the pot.
Make sure the container has adequate drainage besides just the hole where the plant is coming out.