What happens if you run out of Beans?
The official Rio Grand Games  rules cover this eventuality (page 4) the last sentence under Plant Bean Cards


  If the Active Player has no cards in hand, he omits this step.


I have no access to the Amigo Games version, or the German version of the rules. The Game Cabinet site does have a translation:


  Playing Bean Cards - You must play the first card dealt to you on to one of your fields, unless you hold no cards.


You just skip the first step, since you are unable to fulfill the conditions.