The trays are necessary to grow your greens in our growth-set. When ordering a growth-set, you will need to buy either the white trays or the transparent trays. These packages also include the film that is essential for the growth of the plants.
One package includes 1 tray with and 1 roll of film. For each growth-layer that you have, you will need one tray.
This package does not include the plants and electronic components, displayed on the picture.