Saffron is a very valuable medicine and a very goodal herb and a high-quality dye. Saffron is a very valuable medicinal herb and a high-quality dye.

"Medicine" usually refers to a finished product used to treat illness (like a pill or drug), while 药材 refers to a raw medicinal substance/material. Additionally, "good" usually refers to something that is generally satisfactory or effective, while 上好 refers to something of especially high quality or superior standard.

Most of its saffron is exported to Turkey and Spain. Most of its saffron is exported to Turkey and Spain.

The word "of" must be followed by a determiner before a noun when referring to a specific amount, and 'its' specifies whose saffron is being discussed.

Farmers must get up early and work hard to harvest the saffron flowers every November when the saffron fields are in fully bloom. Farmers must get up early and work hard to harvest the saffron flowers every November when they bloom.

This is understandable, but 花朵 refers to the flowers, not specifically the fields. Your native text focuses on the flowers blooming, not a field.

When the saffron fieldlowers of Iran are in full bloom, the entire area seems to be covered with a purple carpet. When the saffron flowers of Iran are in full bloom, the entire area seems to be covered with a purple carpet.

Grammatically correct, but your meaning here shifted as the Chinese says 番红花 (saffron flowers/plants), not specifically "fields."

The picturesque scene attracts thousands of tourists to admire and experience it. The picturesque scene attracts thousands of tourists to admire and experience it.

The problem here is that "admire and experience" need an object ('it').