What makes a plant grow healthiest

Question

What makes a plant grow healthiest, horse manure, coffee grounds or banana peels? I need to know this for my science fair. I need research.

Answer 1

Here are some articles that should help you with your research:
https://www.gardeningknowhow.com/composting/manures/horse-manure-compost.htm
https://www.gardeningknowhow.com/composting/ingredients/coffee-grounds-gardening.htm
https://www.gardeningknowhow.com/composting/ingredients/banana-peels-compost.htm

Answer 2

well horse manur adds nitrogen so does coffee grounds, but banana peels ,potasium but compost does the most good, add all these together win carbon material and boom growth,