These are my answers. Which of it is more acceptable?
1. People are buying plants and people are buying pots. If they buy the two things seperately and put the plant in the pot themselves, then we can talk of buying 'plants and pots' or 'pots and plants.' If we rewrite your answer as 'Every day (in this usage, the two words should be seperated) many people come to buy local plants and pots', then we are saying that both the plants and the pots are local. Perhaps they are, but maybe we need to make a distinction about the origin of one or the other.
- Everyday, many people come to buy local plants and pot.
- Everyday, many people come to buy local plants in pots.
2. Again the two words every and day should be seperated. As written, its not clear whether you mean that people are buying plants that are in pots OR if people are coming in pots to buy plants . Of course it is absurd to imagine that people travel around in pots but in another situation the difference may not be so obvious.
If you mean that the plants are already in the pots when the people buy them, then we (NA) would call them potted plants. 'Every day, many people come to buy potted plants.' If you want to make a point that the plants are local, then say, 'Every day, many people come to buy potted local plants.'
Interested in Language