I can already taste the yummy tomatoes, still warm from the sun because they were picked from the vine just minutes before the meal. But tomatoes can play host to a number of plant diseases as well. Anthracnose, caused by a fungus is a common fruit-attacking disease. Symptoms first become visible on ripe or ripening fruit as small, circular, indented spots in the skin. Another fungus that could attack is Fusarium wilt. This soil-dwelling fungus causes leaf yellowing and wilting that progress upward from the base of the stem. But these are only two of a host of issues that you could encounter. If tragedy strikes your tomatoes, fight back with these five tips for dealing with infested crops.
1. Solarize the soil. Fight pests my moistening the infected area and covering it with black plastic for at least four weeks in the hottest part of the summer. It will make infestation much more difficult in the deadened soil.
2.Plant marigolds. Select a French variety of marigolds to fend off nematodes. Plant the infected area full of marigolds. Grow for about three to four months and then till the area.
3.Rotate crops. Tomatoes should only be grown in the same area every three to four years. If your crops are already infected, only transplant them when they are dry so as not to spread the disease.
4.Water in the morning. Water tomato plants at the base of the plant in the morning rather than the evening to minimize the amount of time that the leaves are wet to avoid fungus infestation.
5.Harvest frequently. Don't leave already ripe fruit on the vine. Pick it immediately to prevent your beauties from getting attacked. This also prevents cracking which can occur if ripe tomatoes have to sit through a hard rain storm.
Source: Organic Gardening