Answer: You didn't say whether you were getting many blossoms on the plant. If you don't have many blossoms, I'd suggest using a phosphorous fertilizer (info on fertilizer below) to increase bloom. If you have many blossoms, but still no fruits, then it's probably a lack of pollination. There aren't as many pollinators (bees, etc.) around as in past years. Try gently tapping and shaking your plants in the early morning, or hand-pollinate with a Q-tip to see if you can get some fruit to set. Or, plant some flowers nearby to attract pollinators.
Here?s some basic info on fertilizer and nutrients that plants require. The 3 numbers on a fertilizer bag refer to the percentage of N (nitrogen), P (phosphorous), and K (potassium) in the bag. There are different formulations for different purposes. In general terms, nitrogen produces lush green growth, phosphorous helps strengthen stems and produce flowers, and potassium keeps the root system healthy. If you're applying fertilizer to fruiting (e.g., tomatoes) or flowering plants, you're not as interested in the plant developing leaves as you are in it flowers and fruit, so you'd use a formulation lower in nitrogen and higher in phosphorous, such as Miracle-Gro's Plant Food at 15-30-15. Bone meal is an organic source of phosphorous. Good luck!
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