Whether it is flowers or vegetables, plug seedling is a fundamental change in modern horticulture, which provides a guarantee for fast and mass production. The plug has become an important tool in the factory seedling production process.

The materials for making plug trays generally include polystyrene foam, polystyrene, polyvinyl chloride and polypropylene. The manufacturing methods are blow molding and injection molding. Common vegetable and ornamental plant seedling trays are made of polystyrene material.

The size of the standard plug tray is 540mm×280mm, and the number of holes is between 18-800 due to different hole diameters. For the cultivation of medium and small seedlings, 72-288 hole plugs are suitable. The hole shapes of the seedling trays are mainly square and round. The square hole contains about 30% more matrix than the round hole. The water distribution is also more uniform, and the seedling root system is more fully developed.