Answer: There are many things you can do to help prevent disease in plants. I think the best suggestion would be to practice good garden sanitation. Be sure to pick up litter from the plant, destroy any leaves that are diseased or have pests, etc. Good air circulation is important also, lots of fungal diseases can occur in areas where plants are crowded. Keep an eye on watering, too much or too little can be inviting problems. Resistant varieties are also a big factor in preventing disease for obvious reasons. Look for disease resistant varieties when you are shopping for plants and seed both in nurseries and catalogs. In catalogs you generally see symbols such as "VF" or "VFFNT" or simply "Disease Resistant". With tomatoes in particular, put them in a new spot every year, and avoid planting them where potatoes have grown. Choose tomato varieties that have flat leaves as opposed to curly leaves, which take longer to dry off after rain and are thus more susceptible to fungal infection.
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