Tree tomato, known botanically as Cyphomandra betacea Sendt, is a species of edible fruit that is in the same nightshade family as the garden tomato, but is not actually a tomato despite its name. Tree tomatoes are woody evergreen shrubs that produce egg-shaped fruit in red, orange and purple.
According to Purdue University's Center for New Crops and Plant Products, though its flavor is slightly resinous and blander than a tomato, the fruit is widely grown in Latin America, where it is used in cooking and as a preserve. To grow tree tomato successfully, your soil must meet specific requirements.
Tree tomatoes require lightweight and airy soil that can easily be penetrated by tender and brittle roots. Lighten soil with amendments of perlite or fine gravel if the soil is compacted or dense. The roots can not tolerate any pooling water in the soil so plant on high ground where excess water in the soil can drain away easily.
The tree tomato needs soil with a high nutrient content. Because the roots grow shallowly, the top 6 to 12 inches of soil should be rich in organic matter. Amend poor soils with a few pounds of aged manure and/or compost to create ideal nutritive conditions at planting time. Topdress established plantings each year with several pounds of compost or aged manure to replenish the soil.
Tree tomatoes benefit from regular applications of complete fertilizer with a N-P-K (nitrogen-phosphorus-potassium) ratio of 5-6-6. This helps replenish the nutrients the shallow roots draw out of the soil. Feed the plants twice each year in spring and summer during peak production. Apply the fertilizer following the dosing directions on the label for the size of plant and planting area. Make a special application of fertilizer supplements in the spring once the tomato tree reaches five or six years of age. Apply two to three pounds of a combination of superphosphate, nitrate of soda and sulphite of potash for each tomato tree plant. These nutrients and micro-nutrients will reinvigorate the surface soil and plants helping to maintain generous fruit harvests.