Baby (worm Size) Snake In Florida Found, Can It Be Poisonous If I Let It Grow Up?

I also just found one of these, although mine seems to be quite docile and doesn't mind being handled.
I caught a baby black racer a few days later but let him go because he was very aggressive.

I believe another name for the snake you and I have is Florida Brown Snake and they do not get much bigger than what you have there according to what I have found online.

Well the image you put it shoes a really poisonous snake.if I was you I would just let it go instead. Well the reason it is aggressive is because it feels threaten and scared.here are some tips to be safe don't go near it,especially don't pick it up.
AND IT'S A HOGNOSE SNAKE...

It actually is a Dekay's snake or a brown earth snake, and it isn't venomous it eats worms and slugs

It could be a Rattle Snake, or something as simple as a Hog Snake snake, which is not poison at all.  Take a picture, and send it to a game warden for I D.

I found a small snake in the garden area today. It was dead, it looked like a baby (about 12 inches long. It seemed to have fused eyes and the mouth was opened. It is a beautiful shade of baby blue or lilac with clear orange-red spots on its back. I can't find it in any description of Snakes in Florida.

I think that a baby worm would be about 12 centimeters long

If a snake is poisonous as an adult, then it is also poisonous as a juvenile. It is not poisonous.