Answer: A brown spot at the bottom of the tomato would be blossom end rot. This is usually caused by fluctuating soil moisture. To avoid the problem, water as needed to keep the soil moist like a wrung out sponge -- never sopping wet and never dried out. Other types of spots all over the tomato would be disease related. Plant varieties with high disease resistance. Disease resistance is indicated by the letters such as V,F,N,T listed on the seed packet or plant label. Also, clean up all the tomato plant debris (leafs, stems, roots, fallen tomatoes) at the end of the fall and put them in the trash. Rotate your plantings so you do not plant tomatoes in the same spot every year; wait three to five years before planting them there again. This will help prevent carryover of diseases from year to year.
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