Early blight. Late blight. Vertcillium wilt. Fusarium wilt. Blossom end rot. Septoria leaf spot. Anthracnose. Tobacco mosaic virus. Root knot nematodes. The list of tomato diseases is long and the symptoms of each overlap making it difficult to determine which particular disease has hit your tomatoes. No matter the disease, the end result is that you don’t have the number of tasty fresh tomatoes you hoped for when you planted them.
There are many things you can do to prevent diseased tomatoes so you don’t have to spend time trying to determine which disease wrecked your crop.
Buy plants or seeds that have been bred to be resistant to some of the diseases. You need not spend time researching this; breeders are glad to tell you right after the name of the tomato. The label will say, for example, Better Boy Hybrid, VFN. The capital letters denote which diseases the cultivar resists. “V” is for verticillium wilt, “F” is for fusarium wilt and “N” is for root knot nematodes. You don’t really have to know what the letters stand for. The more letters after the tomato’s name, the more diseases to which it is resistant.
The next important disease prevention tool is mulch. Many diseases are splashed up from soil. Spread a thick layer of mulch like hay, straw or pine needles starting about two inches away from the stem and cover an area of at least a four foot diameter.
Clean old tomato cages with a 10% bleach solution especially if you have had disease problems in the past. Remove any crispy bits of last year’s leaves that may be stuck to the cages.
Many disease pathogens overwinter in the soil, so avoid planting tomatoes where you had them last year. Don’t plant them where you had peppers, eggplants or potatoes either. Like tomatoes, they are members of the Solanacae family and are prone to many of the same diseases.
When you water tomatoes, try not to get the leaves wet. When it rains, avoid touching the plants until they dry. If you smoke, don’t do so in the garden, and always wash your hands with soap and water before touching the plants. Tobacco mosaic virus can be transmitted to the plants by smokers.
Avoid high nitrogen fertilizers. Excess nitrogen causes too-rapid growth which encourages foliar diseases. It can also inhibit blossom formation and pollination and delay ripening.
Keep the area around your tomatoes free of weeds and pull volunteer tomato plants that sprout from last year’s seeds. If you see signs of disease on the lower leaves, pull them off and put them in the garbage, not the compost pile. This may slow the disease and allow you to get at least a partial harvest. Tomatoes harvested from plants with diseased leaves are perfectly safe to eat.
Leave a Reply