The ideal soil type for growing tomatoes is slightly acidic, well-drained, and loamy. Tomatoes should not be planted on land where peppers, eggplant, or potatoes have been grown in the last three years to avoid nematode infestations or residual herbicides.
Depending on the area, fumigation may be necessary to control pests, weeds, and some diseases. Proper staking/caging and irrigation is important for good yields.
Pests & Diseases
Aphids feed on leaves making them curl and become distorted. Loopers also feed on foliage, creating ragged holes. White flies feed on the underside of leaves turning them black. Tomato russet mites, which cause bronzing and defoliation, are very difficult to detect.
Other pests to look out for include flea beetles, cutworms, leafminers, stink bugs, and the aforementioned nematodes in soil. Tomato pinworms, tomato fruitworms, and vegetable weevils also pose a threat.
Botrytis grey mold turns leaves brown with grey mold noticeable on stems and leaves. Fusarium wilt causes foliage to yellow and wilt. Blossom end rot will appear as dark, flattened, or sunken areas on the blossom end of the fruit and can result from insufficient calcium in the soil to reduce effects of fertilizer. Blight (both early and late), alternaria, big bud, buckeye rot, white mold, canker, and powdery mildew can cause problems as well.
Storage & Packaging
Mature green tomatoes are typically harvested by hand and sorted by size, graded, and placed in temporary cold storage.
Optimum temperatures for mature green tomatoes are 55 to 60°F; for light red (categorized as USDA Color Stage 5, described as “Light red: 60% to 90% of the surface is not green; in the aggregate, shows pinkish-red or red”) in the 50 to 55°F range; and for firm-ripe (USDA Color Stage 6, “Red: More than 90% of the surface is not green; in the aggregate, shows red color”), 44 to 50°F for 3 to 5 days is optimal.
Tomatoes held at 50°F for longer than 2 weeks or at 41°F for longer than 6 to 8 days are vulnerable to chilling injury.
Optimum relative humidity is 90 to 95% but extended periods of higher humidity may encourage the growth of surface mold and/or other concerns due to excess condensation.
Ethylene is typically applied to mature green tomatoes for uniform ripening. Because ripening tomatoes produce ethylene themselves at a moderate rate, storage and/or shipping with ethylene-sensitive commodities should be avoided.
References: Texas A&M Agri-Life Extension, UC Davis Postharvest Technology Center, University of California Agriculture & Natural Resources, University of California Cooperative Extension, University of Tennessee, USDA.