Okay kiddo, let me tell you about Franklin Hiram King. He was a very smart man who loved to study farming and how to make crops grow better. He figured out that if you give plants the right kind of food, they will grow bigger and stronger.
Now imagine you're playing with some Lego blocks. If you have the right pieces, you can build a really cool tower or spaceship. But if you have the wrong pieces, your creation might fall apart. It's the same with plants. If you give them the wrong kind of food, they won't grow very well.
So, Franklin Hiram King wanted to help farmers make their crops grow really well. He studied different kinds of dirt or soil and how they affect plants. He also looked at what kind of food plants need, like nitrogen and phosphorus.
By understanding how to make the soil and plants happy, Franklin Hiram King helped farmers grow better and more food. And that's pretty cool, right?