Tomato Home Gardening

The home gardener needs to follow the following 6 procedures in order to produce a continuous yield of high quality tomato fruit over the entire growing season.

1. Site Selection
That site receiving full morning sun and then partially shaded from afternoon sun is desired. Having the tomato plant exposed to direct afternoon sun can reduce yield and quality of fruit as well as shorten the productive growth period. This is primarily true in the southern regions and may equally apply in those areas that have minimal cloud cover during the day. Near areas that are regularly treated with pest chemicals, downwind of industrial plants, dusty roads, etc., is not a suited site for growing tomatoes.  For irrigation, a reliable clean water supply should be available at the site.

2. Soil Preparation
Soil water pH and level of essential plant nutrient elements will determine plant vigor, the ability of the plant to remain productive under stress. Have the soil tested (sample to a depth of 6 to 8 inches) to determine its fertility status as well as what amendments are needed to correct insufficiencies. Following the recom-mendations given, work those amendments specified into the soil to a depth of 6 to 8 inches, the deeper the better. The tomato plant is deep rooted and will significantly benefit from a uniform depth of soil. If available, add compost to the same soil depth to create a loamy soil structure, particularly if the soil has a sandy texture or high clay content. Avoid excessive compost additions that can result in cool wet soil conditions, make the soil slow to drain, and may add unwanted nutrient elements that can adversely affect the plant due to imbalance or excessive levels. If the soil has been limed and fertilized as recommended, no additional amendments should be needed during the growing season. If tomato was the previous crop, select another area in the garden as the soil microbial population may be detrimental to good plant root growth. Be sure that the soil is free of nematodes. If only a small area is being prepared, the soil area treated should be18 inches in diameter

3. Variety Selection
Select a variety that is adapted to the local climatic conditions, has been genetically selected as being disease resistant, and will produce the fruit type desired (beefsteak, cherry, Roma, etc.). With the recent interest in heirloom varieties, selection may be challenging as some heirlooms may not have certain disease resistance characteristics, and may be easily affected by moisture stress, sensitive to either high or low air temperatures, and easily affected by soil fertility conditions, that is, either unresponsive to high soil fertility, or adversely affected, resulting in poor fruit yield and quality. For fruit production over the entire season, select an indeterminate variety.

4. Seedling Transplants
The quality of transplants will affect plant growth and eventual fruit yield. The transplants selected should have been conditioned prior to setting in the garden soil, rooted in their own seedling container and stocky in physical appearance.  Set the transplant into the soil slightly below the soil line in the germinating cell. Add water so the surrounding soil is just moist, but not wet, as over-watering at this stage will slow root development into the surrounding soil. At this stage, the plants are susceptible to frost and cool air temperature injury; therefore protect when such conditions occur.

5. Soil Moisture Control
Place in the ground to a depth of 2 inches, a 4-inch diameter pot about 2 inches from the base of the plant. When watering, add sufficient to fill the pot. The hole in the pot should be relatively small so that the added water will flow slowly out of the pot. Keeping the soil moist (not wet) around the roots of the plant at all times is better than only watering when the soil becomes dry. If the plants are under moisture stress, fruit yield and quality will be poor. Fruit blossom-end-rot (BER) will occur even if the soil fertility conditions are adequate, when moisture stress occurs. Watering just to keep the soil surface wet is usually not sufficient when the tomato plant is in its fruiting period.  Depending on the occurrences of natural rainfall, do not irrigate if it is done intermittently as the tomato plant does not easily adapt to changing soil moisture conditions. Keeping the soil “wet” is as detrimental to plant growth as cycling moisture con-ditions.

6. Plant Management
Remove axial and fruiting stem suckers. Cluster prune by removing fruit that are misshapen, or will not eventually mature, a procedure that will keep the plant fruit productive over the entire fruiting period. Leaving small slow developing fruit on the plant will reduce the yield and quality of produced fruit. Remove diseased or insect damaged leaves when they initially appear. Leaves below the last fruit cluster harvested should be removed by cutting from the main stem. Keep the plant upright by tying to a support stake or place the plant in a surrounding cage.

7. Other Factors
Following the procedures described above, it should not be necessary to make amendments in order to sustain the tomato plant in a fully fruit productive condition over the entire growing season. Over-fertilization can be as detrimental to plant growth as an insufficiency. For example, excess nitrogen (N) will reduce fruit yield and quality by stimulating vegetative growth as well as making the plants more susceptible to disease and insect infestations. Plants that are actively growing are less likely to be affected by changing weather conditions as well as disease and insect infestations. Heat stress, inadequate or excessive watering, and over fertilization are causes for flower abortion. Low soil pH can be factor in the occurrence of BER and magnesium (Mg) deficiency, whose deficiency may not appear as visual leaf symptoms, but can result in low fruit yields. Foliar-applied calcium (Ca) is ineffective for controlling blossom-end-rot (BER).  Placing mulch around the plant can be effective in reducing water loss from sandy soils, but can keep the soil cool and wet, thereby retarding plant growth.