Green Amaranth

After I started working in the city, I also ate green amaranth from time to time, but the amaranth I bought in wet markets felt a little different from {the one | that} in my village, though they looked very similar.

“The one” doesn’t feel natural to me, but it’s not wrong.

I checked it carefully by smelling (it), touching (it) and {observing | looking at it} it.

“Observing” is more commonly used for things that might move or change in some way. You could omit all but the last “it”.

Hopefully it's going to bring back to me the memories of my childhood.

or: …to bring memories of my childhood back to me.

It was almostpractically the only vegetable we ate during summer.

We usually ate it often for lunch because it was often cooked with noodles.

After I started working in the city, I also ate green amaranth from time to time, but. But the amaranth I bought inat the wet markets felt a little different from the one in my village, though they looked very similar.

Hopefully it's going to bring back to me the memories of my childhood.

It was almost the only vegetable we ate during the summer.

Seemingly, "during summer" is technically correct. However, adding "the" just feels right to me. I made sure to look up "during summer vs. during the summer" to see if there is any merit to posting this correction, and it seems like there is already a discussion on StackExchange on this exact topic (https://english.stackexchange.com/questions/37738/during-summer-vs-during-the-summer#37744). According to one reply, "during the summer" is used much more frequently than "during summer."

It grew very fast in summer, but it needed water almost every day.

No change suggested

You might very well be correct about the use of "in summer" here: https://hinative.com/questions/5286388 https://grammarhow.com/in-summer-or-in-the-summer/ (Might be AI?)

After I started working in the city, I also ate green amaranth from time to time, but the amaranth I bought in the wet markets felt a little different from the oneones in my village, though they looked very similar.

The amaranth in my village looked wilder, stronger, and tougher.

No change suggested

I almost corrected this to "amaranths," but it turns out that the plural of "amaranth" is also "amaranth" in many contexts. If you were to refer to multiple types of amaranths, then the plural "amaranths" would probably be used instead. https://www.wordhippo.com/what-is/the-plural-of/amaranth.html

I checked it carefully by smelling it, touching it, and observing it.

Ah, the good ol' Oxford comma. Personally, I advocate for using the Oxford comma in any case, but I think it's especially important in this case because you're listing actions, not mere nouns. However, the Oxford comma is a much-debated topic in English grammar, and there are likely many native English speakers who would agree with your omission of a comma.

Hopefully, it's going to bring back to me the memories of my childhood.

The "to me" might be unnecessary, but it's not incorrect.

We often ate it often for lunch because it was often cooked with noodles.

You are not wrong but putting "often" here improves readability.

After I started working in the city, I also/still ate green amaranth from time to time, but the amaranth I bought in wet markets felt a little different from the one in my village, though they looked very similar.