The invention relates to a plant growing device comprising cultivation cover, which is formed of a framework (10) of the cultivation cover and panels (11) to be mounted to the framework (10) and fastened with magnets, which panels (11) are provided with frames of metal or wood or plastic, open on all sides of the cultivation cover, are fully detachable on all sides of the framework (10) and are mounted in place by lifting one panel into each frame of the frame work (10) of the cultivation cover from outside the device, which framework (10) of the cultivation cover is of metal or wood or plastic and which consists of separate interconnected frames that form all sides of the framework, the frames being interconnected by fastening members, and inside of which device a material selected according to the intended use, climate type or season is installed, and which panels are combined from one or more different types of panels (11). The device is suitable both for fully organic growing of plants and for intensive gardening.