Not sure of your zone but basil, cilantro and dill are all annuals which means they will die after flowering and going to seed in one season. You can prolong them by pinching off the flowers. Parsley is a biennial and will go to seed the second year. Oregano is a perennial and will live as long as it doesn't freeze. Tomatoes are also annuals. Many times when plants go to seed, new baby plants will come up so watch for the new babies next year. I fertilize with compost and fish emulsion (both are organic). I am an herb gardening fanatic- love my herbs!
ETA: Obviously you don't want to pich off the flowers of fruiting plants like tomatoes and peppers since that's where the fruit comes from. I don't know much about peppers but we've had a tobascco and jalapeno for over a year and both are still doing great.
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"If you have men who will exclude any of God’s creatures from the shelter of compassion and pity, you will have men who will deal likewise with their fellow men." — St. Francis of Assisi, 1181-1226