How do I ask my neighbour to stop criticising my garden in front of visitors?

My neighbour pointed at my artificial flowers while my sister was beside me and said, “You know they look plastic, don't you?”

They are plastic. That is why they survived two trips away and the week I forgot to water everything else.

He is a keen gardener and has offered cuttings before. I thanked him but declined because I don't want more plants to maintain. Since then, he has made little comments about my pots being “the easy option.” I usually laugh. On Sunday I said, “Some of us have other things to do,” which was needlessly rude about a hobby he loves.

I don't want advice about making the flowers more convincing. I want to stop feeling that every visitor to my front step is about to get a review of my gardening standards.

Should I apologise for the hobby remark and ask him to stop the running commentary? I worry that saying the flowers are staying will turn a small irritation into a declaration of war between two hanging baskets.