A common practice among tomato growers is to continually supply their tomato plants with stakes or cages to grow vertically. Training a tomato plant vertically not only makes harvesting and care easier, but also decreases the chance of poor air circulation, which can lead to disease. If you're short on garden space, however, a newer way to grow vertically is to grow a tomato upside down. Once set up, an upside-down tomato is easy to manage.
Create a hole in the bottom of your bucket with a jigsaw in the center about 3 inches around, if you are making your own basket. Fill the bottom inch or two of your bucket or planter with 1 inch of peat moss, keeping the moss from going out the hole in the center.
Hang the bucket or planter where you want it to go, standing on a ladder if necessary to reach both the top and bottom of the planter. Leave at least 5 feet of room between the bottom of the planter and the ground.
Strip a few of the leaves off the bottom of the tomato seedling's stem, leaving an inch or two at the top full of large leaves. Remove the pot from the seedling and insert the root ball up into the hole from the bottom.
Adjust the seedling so the top 1 to 2 inches of the plant stick out from the bottom with the remainder in the bottom of the planter. Hold the seedling in place with one hand inside the bucket.
Fill the bucket with potting or garden soil with your other hand until the seedling is secure and not going to slip through the hole, and let go of the seedling. Pack the soil as needed to keep it from coming out of the hole as well.
Fill the rest of the bucket with soil up to 3 inches from the top. Layer 2 inches of mulch over the soil to help with moisture control.
Water the planter from the top with enough water to really moisten the soil inside, but you don't want to see an excess of water pouring out the bottom of the planter. Water again any time the soil along the bottom feels dry to the touch. Allow the tomato plant to grow straight down with some curving up toward the sun being normal.
Harvest ripe tomatoes as soon as possible to keep the plant productive.