Question

add a comma, semicolon, or colon if needed. otherwise, submit the text without any additional punctuation.
mr. yamada grows a variety of medicinal herbs in his garden chamomile, echinacea, lavender, feverfew, and lemon balm.

Explanation:

A colon is used here to introduce a list of the medicinal herbs that Mr. Yamada grows. The part before the colon ("Mr. Yamada grows a variety of medicinal herbs in his garden") sets up the context, and the part after lists the specific herbs, so a colon is appropriate to connect them.

Answer:

Mr. Yamada grows a variety of medicinal herbs in his garden: chamomile, echinacea, lavender, feverfew, and lemon balm.