Umm, you have no base defenses? Have to say that it is on you if you choose to just wander around in the plains and make a farm with no way to protect it or you. You can trench it and you can make an earthen wall or do both. And no that is not cheese or exploit, it is a base function of learning to play the game. With historical backup. May I introduce you to walled cities, all over the world that protect that which is valuable from those who would like to ruin it. Even Vikings of yore walled their towns, fields.
Put down workbenches so that their area of security overlaps.
Or... you can hope to be lucky, and we know how that has worked out. Important lesson.