Translation:The flavor of the wine depends a lot on the time.
"the flavor of wine depends a lot on its age" would be a much more natural way in which to express this idea in English. We would never use "time" to express this concept, unless we said something like the wine had spent a lot of time aging, or a lot of time in the cask.
It's not that duo can't make up its mind. It's that Spanish uses definite articles differently from English. https://www.spanishdict.com/guide/using-the-definite-article-in-spanish
mucho can be an adjective or adverb (http://www.spanishdict.com/translate/mucho).
EDIT - what I've noticed about Duolingo is that when they use "mucho" they only seem to want "a lot" as the translation, whether it's an adjective or an adverb. "A lot" is not always my first choice when constructing a sentence, and it bugs me to always have to use it to get my translation accepted. I used "really depends" here instead of "depends a lot" and it was rejected. I will report it, as I think Duolingo should be more flexible with this modifier.
A agree with most comments except for "the weather". I can´t imagine that this would have much to do with the meaning of the sentence. On the other hand, I can´t imagine "on the time" making sense either. I think "vintage" or "age" would be much more accurate a translation. I used "age" and it wasn't accepted. I will report that it should be.
I disagree. You don't HAVE to say what something depends on. "Do you like soup?" "It depends on the ingredients." "Always?" "It depends a lot of the time. I like chicken noodle no matter what." So, in English, there's no hard requirement that the word "depends" is followed by a phrase starting with "on." Something can depend "a lot of the time." And in Spanish, "del" translates to "of the," so I feel like "The flavor of the wine depends a lot of the time" is a valid translation.
In fact, saying that the flavor of the wine depends a lot on the time means that the flavor of the wine might be different at 6:00 than it is at 8:00. Translating "del" to "on the" makes more sense when translating "tiempo" to weather. But when translating "tiempo" to "time," you almost have to translate "del" to "of the."