Shoud I use "for"?

Hello everyone. I would like to know if anyone could please help me with this grammar doubt.

Here are two sentences:

- "There is nothing but flowers as far as the eye can see."

- "There is nothing but flowers for as far as the eye can see."

The questions are: does it make any difference in using "for" or not? Is one sentence more correct than the other? If so, which one and why?

I have seen similar sentences in which "for" was not used, but I have also heard the opposite.

Thank you in advance.