The present invention is directed to a plant growth system comprising: (a) a container having a top opening and an inner volume； (b) a receiving structure inside the inner volume of the container, wherein said receiving structure is form-stable, and comprises or essentially consists of mineral wool； (c) a plant receiving portion formed by the receiving structure for receiving a plug comprising a plant through the top opening of the container into said plant receiving portion and holding it in place； and (d) one or more volume space(s) free of mineral wool.
