Preventive Measures when and what?

[Wolfie1038]

I feel really "Rookieish" (is that a word)? Last year I was plagued with Early Blight, leaf spot, and Late blight. While the fruit continued to grow, the plants looked TERRIBLE! I want to avoid that this year BEFORE it starts. I have both Daconil liquid concentrate AND Neem. I am relatively new to this and I'm not sure what to use and whento use them. I am reading a lot and I think Neem is for bugs and Daconil is for fungus, etc. Is that right? I put my plants in a couple weeks ago and they look great but I wanted to know when I should start "Preventive" measures and with what. Thanks in Advance.