Learn Italian: Il pomodoro che il contadino raccoglie tocca la terra. - The tomato that the farmer gathers touches the earth.

Here, che is the direct object of the relative clause. It stands in for the tomato (il pomodoro), which is the thing being gathered. The subject actually doing the gathering is the farmer (il contadino).

In English, I could just say 'The tomato the farmer gathers...' Can I drop che in Italian?

No, you can never drop the relative pronoun che in Italian. While English lets you skip the word 'that', Italian grammar strictly requires it to connect the two parts of the sentence.

Why is the main verb tocca so far away from its subject, il pomodoro?

The relative clause (che il contadino raccoglie) describes the tomato, so it must be placed immediately after il pomodoro. This splits the main sentence (Il pomodoro tocca la terra) into two parts. You will see this sandwich structure a lot when using che.

What is the infinitive of the verb raccoglie?

The infinitive is raccogliere, which means 'to gather', 'to pick', or 'to collect'. It follows the regular -ere verb pattern in the present tense, making the 'he/she/it' form raccoglie.