The number and variety of tomatoes currently on the market and maintained through personal seed saving is a testament to the importance of this botanical fruit that is most often referred to as a vegetable. Tomatoes are a great source of vitamins C and A, as well as lycopene, which is shown to be beneficial to cardiovascular health. There is both art and science in producing the homegrown tomato.
Gardeners must make two important decisions related to the types and cultivars of tomatoes for the home garden. The first is related to the determinate or indeterminate habit of the plant. Determinate tomatoes are those that will “top themselves.” This means that the primary growing tip is genetically programmed to form a flower at a certain point, and the plant does not grow any taller. Determinate tomatoes are typically shorter and can be easier to manage in the garden. Tomato fruit are set in a relatively short period of time and then ripen in a concentrated harvest interval – often four to five weeks.
Indeterminate varieties continue to grow and produce both new leaves and new flowers from their primary growing point. This continued growth means they will be taller and continue to set and mature fruit through the summer and fall. Unless damaged by insects, disease or environmental stress, indeterminate tomatoes will produce until killed by low temperatures in the fall. So, they will require taller stakes to provide good support.
When choosing between determinate and indeterminate tomato plants, consider your intended use. Determinate plants may be best for more concentrated yield for canning, while indeterminate plants may produce over a longer period of time for fresh eating. Also consider the time available to invest in plant support, training, disease and pest control and picking throughout the season.
The second decision important in selecting tomatoes for the home garden is the specific tomato cultivar. Hundreds of tomato cultivars are commercially available to home gardeners with many more saved by residents for personal production. The most important considerations are the disease resistance and the gardener’s preference in terms of fruit color, size, shape, taste and days to harvest.
Tomato cultivar selection is important, but the selection or production of high-quality plants is also crucial. Tomato fruit yield and garden performance begin with high quality plants. Tomatoes can be direct seeded, but due to the 90-120 days from seeding to harvest, transplants are common for garden tomatoes to reduce the time to harvest. Because of this convention in both commercial and garden production, the time to harvest listed in cultivar information will be estimates of time from transplant to harvest of ripe fruit.
Whether grown or purchased, tomato plants should be stocky with strong root systems. Plants that have been grown with suboptimum light or improper temperature conditions will often be “leggy” or have thin stems with larger distances between leaves. Also look for transplants that have a healthy green color and are free from damaged or yellowed leaves that indicate insects or plant stress. Inspect leaves for any sign of disease.
Avoid purchasing transplants grown out of state, as these have been a major source of disease problems in Tennessee gardens. Purchase locally grown transplants, if possible. Transplant-borne diseases such as bacterial spot are difficult or impossible to control once introduced into the garden.
Tomato plants are commonly six to eight weeks old when ready for garden planting. All transplants should be “hardened off” before planting. This term refers to slowly subjecting plants to outdoor conditions to lessen their stress at transplant and help them to better handle the sun, wind and temperatures they will experience in the garden. Many garden centers will have plants that have been through these conditions to enable them to have the best chance of transitioning well to your garden environment, but it can be a good idea to ask what the recent conditions have been when buying plants.
For more information, contact the UT-TSU Extension Office in Wilson County at 615-444-9584. You can also find us on Facebook or visit extension.tennessee.edu/wilson.
The University of Tennessee Extension offers its programs to all eligible persons regardless of race, color, national origin, sex, age or disability and is an Equal Opportunity Employer.
Through its mission of research, teaching and extension, the University of Tennessee Institute of Agriculture touches lives and provides Real. Life. Solutions. ag.tennessee.edu. Ruth Correll, UT Extension-TSU Cooperative Extension agent in Wilson County, may be reached at 615-444-9584 or firstname.lastname@example.org.