It is assumed from a usage-based perspective that learner language constructions emerge from natural language use in social interaction through exemplar learning. In L1, young learners have been shown to develop their constructions from lexically specific, formulaic expressions into more productive, abstract schemas. A similar developmental path has been shown for L2 development, with some exceptions. The aim of the current study is to explore to what extent the default assumption holds for L2 learning. The development of two constructions was traced in four adults learning L2 Finnish. Free-response data, collected weekly over a period of 9 months, were used to investigate the productivity of the constructions. The results show that, contrary to the traditional assumption, L2 learners do not start off with only lexically specific expressions, but that both lexically specific and more productive constructions are used from the beginning. Our results therefore suggest that, for educated adult L2 learners, the schema formation can happen rather quickly and even without the repetition of a specific lexical sequence.