Answer: You sound so discouraged. Gardening is supposed to be fun! Tomatoes require plenty of sun. As for soil, they will grow in just about anything you throw at them. That isn't to say that amending your soil is a bad idea.
I am always in favor of adding compost and/or manure to the soil prior to planting. Dig it in to a depth of 8-10 inches. Uniform watering is the key to nice fruit. Even watering can prevent leaf-end roll, blossom end-rot and "cat-facing".
It is OK to plant tomatoes in the garden when the temperature is a consistent 50? F, but plants won't begin to set fruit until the overnight low is regularly above 55?. Plant tomatoes approximately 2 to 3 feet apart from each other. Indeterminate types will need support but determinate types will grow into a small bush and won't need to be staked or tied up.
When shopping for tomato plants, be sure to pick out healthy plants with no yellowing or speckling on the leaves (fusarium or leaf spot). If you're not sure what tomatoes you want or need, checking the tag can be a big help in selecting a good tomato. Look for a string of letters on the tag. They denote resistance to diseases.
Hope this information helps you grow a wonderful harvest!
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