The tomato tree, also known as a tamarillo, is native to South America. It was introduced to the United States in 1913 and was first grown in California. Because it thrives in subtropical climates, the tomato tree does well in humid locations. Take care to protect this tree from heavy winds and frost damage. With proper attention, a mature tomato tree may produce between 40 and 60 lbs. of fruit each year.
Select a site in your garden in which to plant the tomato tree. Choose an area with full sun that is protected from heavy winds. Make sure the site has no standing water or potential for flooding.
Till the soil with a garden tiller to a depth of 2 to 3 inches. Add 3 to 4 inches of organic matter such as compost to the area and till again to mix the matter completely into the soil.
Dig a hole 2 to 3 inches deep and 2 to 4 inches wide with a shovel. Place the tomato tree into the hole so that the roots are just underneath the soil. Cover the plant with dirt. Allow 6 to 8 feet between each tomato tree and 10 to 12 feet between each row of trees.
Water the plant with a garden hose. Soak the roots completely but do not let the soil hold water. Wet the area in a 2-foot radius around the base of the tree.
Add a layer of mulch 4 inches deep around the base of the tree. Use pine straw, tree bark or cypress mulch. Cover the area up to 3 feet in area around the tree.
Place a 6 to 8 foot tall trellis behind the tomato tree for support. Begin 6 inches from the tomato tree. Set the trellis on the ground and mark the location of each supporting leg. Dig a hole 2 feet deep at each mark with a shovel. Place the trellis legs into the holes and cover with dirt. Press the soil firmly around the legs to hold the trellis in place.
Train the tomato tree to grow upright. Tie a strip of florist's wire around the branch to secure it to the trellis. Do not twist the wire too tightly or else it will cut into the tomato tree's branches. Tie two or three of the branches to the trellis in this manner.
Fertilize the tomato tree with a fertilizer that has nitrogen, phosphorus and potassium. Sprinkle 1 lb. of this mixture around the tree after planting and again in fall and spring.
Prune diseased and unruly branches from the tomato tree in late summer with pruning shears. Prune the tree annually or as needed after the initial pruning.